Micro Fight Chassis MK 3 ALPINE

Height 5.00
Width 9.00
Depth 1.00
Color None Selected Required


THE MK3 has been discontinued and has been replaced with the MK4. We currently hold a limited stock of Multicam ALPINE. ALL OTHER COLORS ARE OUT OF STOCK. 

*** MK3 Chassis require the updated Rifle Insert Mk3 for proper operation. All other previous generation components are cross compatible.***



The NEW Micro Fight Chest Rig Mk3 is designed to be extremely efficient, modular, and lightweight. The Micro Fight works seamlessly with our accessories suite which offers nearly endless configurations. The addition of soft loop Velcro in both pockets enable you to put mission essential items where you want them based on your individual needs. The improved profile allows for the use of six 5.56 x 45 style magazines or four 7.62 x 51 magazines or any combination of rifle and pistol magazines. The 4” x 9” field of hard loop Velcro on the back of the rig allows for solid integration with accessories such as the S.A.C.K. pouch or after market plate carriers. Just like the Micro Fight Chest Rig Mk2, the Mk3 is designed to scale from low visibility to high profile at a moment's notice.


Unmatched Versatility  

The Micro Fight Chest Rig sports a host of accessories like no other system. The user can select from any of our accessories to meet operational requirements. The platform is lightweight and small while still allowing you to carry multiple types of munitions and equipment. Examples include rifle and pistol Magazines, 37/40mm grenades, flash-bangs, multi-tools, flashlights, medical supplies, and breaching equipment.

Stand Alone System

The Micro Fight Chest Rig was designed to perform as a stand-alone system. It can be configured for wear in low visibility environments that require minimal printing through clothing with maximum equipment storage. It can also be configured for high visibility operations where a full spectrum of equipment is required.

Placard Configuration

The Micro Fight Chest Rig was designed to work seamlessly as a "Placard" for plate carrier systems. Simply remove the 1 inch side release buckles and attach the system via the hard loop Velcro located on the back of the system to you plate carrier. This configuration allows for profile expansion or reduction as mission requirements change. 

NOTE: The CHASSIS is part of the Micro Fight Chest Rig System. This item does not include shoulder straps, back strap, half or full flaps, magazine inserts, or any other accessories. Additional components are required for proper use. If running as a stand-alone system, shoulder straps, back strap, magazine inserts, and possibly full or half flaps are needed. If running on a plate carrier, back strap, flap(s), and magazine insert(s) are needed. 

Some images shown with optional accessories, sold separately.

Product Reviews

Score: 5 out of 5 (based on 47 ratings)
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Micro fight chassis MK3
Written by Chad on Mar 12th 2019

Great kit. I recently used this fitted with the fat straps, back strap, and 2 mag inserts in a 2 day carbine class. It worked great. Mags stayed put but weren’t hard to pull out. I kept the rig loaded with 5-6 rifle mags and it was comfortable to wear all day.

You only need one rig, because it’s every rig.
Written by Caleb Fuller on Dec 2nd 2018

I’ve had my MK3 for about two years now and haven’t found a single complaint. I’m an average build 6’ my brother is a tall lanky 6’4” and his buddy is 6’3” and yoked. We all can put this thing on adjust it slightly and bam it’s ready to rock. If you can’t set up a micro fight rig in a way that you like then you will never find a system to use. It has to be one of the most modular well rounded well made rigs I’ve seen. Just look at how many companies tried to copy it but can’t live up to the OG. Can’t wait for more kick ass Spiritus gear.

The one rig to have if you could only have one.
Written by Jack on Nov 26th 2018

The micro fight will do anything you need it to do, it is compact, adaptable, and scale able. Construction is top notch. Never had a problem with mine.

Professionally constructed slick gear
Written by M39 on Nov 5th 2018

slammin’ salmon

The Only Thing you will ever need.
Written by Kenneth Lyon on Oct 8th 2018

I bought the Mk3 because a friend showed it to me of how modular it is. Depending on what you are doing you can set it up for literally any firearms you have. This piece was the missing link to optimize my kit, and Spiritus has delivered. If you have the expander wings, you can carry a max of 10 AR15 mags, 8 AKs/.308 mags, and maybe 12 pistol/smg mags. The 2nd best part, it uses the industry 1" buckles, so you can add it to a plate carrier that has QASM clips for even further versatility. Pros: - Its a God sent tactical piece of kit all of us need. Cons: - Whoever reads this doesnt have one yet.

All in all, great product, I'd recommend this to anyone for any job
Written by @TheJacobParable on Sep 17th 2018

Spiritus Systems has created a product that brings a functional platform to meet the demands of even the most peculiar of jobs. Their unique system allows for complete customization of your plate carrier or chest rig set up and is both easily removable, swapable, and tacti-cool. Pros: Light weight Customizable - the mag inserts as well are great, they have amazing retention, and will not release a mag until you need one. Many color options (although Atacs IX would be better) Affordable Cons: When using on a Crye JPC 2.0 the Velcro on the back of the spiritus Systems chest rig doesn't hold on to the plate carrier as securely as I would like. And although it has never fallen off, come undone or caused any issues, it's more of a peace of mind thing. I wish the Velcro would seat completely onto the plate carrier. Another con, specifically referring to the black multicam version, is the front of my chest rig has a big yellow spot on it. Just unlucky I suppose that the pattern lined up like that. Lastly, I wish I had the ability to choose between elastic mag inserts and shell mag inserts for easy re-indexing my magazines. This is personal preference of course and isn't optimal for every situation, but that's part of what's so great about this system, is the variety. So maybe somethings to consider in the future, Atacs camo (specifically IX), shell mag inserts as well as elastic ones, better rear Velcro, and better printed multicam Velcro for the front. All in all, great product, I would recommend this to anyone, for any job.

Micro Fight MK 3
Written by Justis on Sep 14th 2018

Awesome piece of gear, perfect for stand alone or on my Crye JPC. Highly recommend.

Micro Fight Chassis MK 3
Written by Ron on Aug 20th 2018

great addition to my gear, awesome product and superior quality

Written by KLKR8 on Aug 14th 2018

perfectly compact, stitched to perfection, solid piece of gear. Couple of the first things that popped in my head, looking forward to running it more.

Top Notch
Written by Darrell E Thompson on Aug 9th 2018

Solid piece of kit. Love of its put together, very well thought out and designed.

Micro Fight
Written by Michael on Jul 12th 2018

The Micro Fight is, hands down, the most versatile carriage system I've used. Over the past year, I've put it through 2 Run N Gun biathlons in the chest rig configuration and have worn it through SWAT school as a placard on my plate carrier. When I'm on duty, it rides shotgun in the placard configuration in conjunction with a SACK pouch filled to the max with trauma gear. If your duty carrier accommodates it, it's a great way to plus up while on patrol in the event of active killer, barricaded subject, warrant service, or other calls where you may be away from the patrol unit for a while and have to take it all with you. If you're a SWAT/SOT guy and find yourself playing multiple roles from one mission to the next, it's easily convertible beforehand to your mission requirements, or set one up for specific duties depending on your team structure and your role. Well made in the USA by combat vets, Spiritus gear is where it's at.

Written by Ryan on Jul 6th 2018

Very versatile and well made, I love that I can set it up how I want.

Incredibly Simple - Simply Incredible
Written by Evan on Jul 2nd 2018

This rig is exactly what I wanted it to be: a lightweight, easily carryable and transportable option that only carries everything I need. For my purposes, I don’t need much more space than this, and if I needed to bring hydration, I could attach a seiftclip camelback. I love that this is seiftclip so that when I get a platecarrier, I’m ready to go without needing to buy additional pouches. Recommended strongly.

Best Rig!
Written by Mark on Jun 23rd 2018

Hands down the most versatile chest rig on the market. Very comfortable and well made. You will not be disappointed!

Top-notch modular chest rig
Written by Frank on Jun 4th 2018

The modularity of this chest rig is fantastic, and the small profile makes it perfect for mounting to my plate carrier with the help of some swiftclips.

Perfect For Low Vis
Written by J McCaskill on Jun 1st 2018

Awesome little chest rig. The modularity of the design allows for adaptability in a minimalist package. The materials used and craftsmanship of the assembled product are second to none. Perfect for fighting light. Keep up the good work.

excellent and modular
Written by Frank on May 30th 2018

This rig is super versatile and yet also capable of being super minimalist. I have worn this rig clipped on the front of my carrier, and as a stand alone system. The quality is top notch. I am currently running this with one rifle mag 2 pistol mags, and a basic array of needed tools. Leatherman, headlamp, and a few other little things.

Written by Danny Conley on May 27th 2018

I love the multicam black, beautiful design. The stitching is top notched, I just like how many configurations can be done with all the separate components based on your individual mission requirements. Excellent product would very highly recommend this to any one. Their service is fast and dependable. Just received my double pistol mag insert and half flap in multicam black of course and have to say the fit and finish is outstanding. Plan to build another soon. Just ordered my triple rifle mag insert couldn’t wait. Spiritus products is excellent!

Written by Christian Caldwell on May 7th 2018

Sleek, lite, and very user friendly. I just have to find a matching plate carrier that I can clip it to.

Micro Fight Chassis MK 3
Written by ROBERT CHAN on May 6th 2018

If you're look for a very minimalist style chest rig... LOOK NO FURTHER!!

Simple. Functional. Dope.
Written by Tony on Apr 23rd 2018

Really simple design, easy to install. A very modular design that's robust enough to configure to most users' needs. Excellent construction and good quality materials.

Micro Fight Chasis MK3
Written by Hector on Apr 21st 2018

I love this chest rig. I like and have the Haley strategic D3CRX, however, this is a much smaller package that is scalable. I love the fact that it is perfect for my civilian uses at the range or on the farm. I'm a portly guy and this versus my belt rig; ill go with this system over a belt system just due to the fact that it's just a smaller package and fits my body better overall.

versatile af
Written by Carlos on Mar 29th 2018

fits perfectly on my slickster

Micro chest rig
Written by Adam on Mar 17th 2018

Used this today on a hike climbing Mount Wheeler in NM. WITH THE fat straps and sack pouch. It worked perfectly for me to be able to access my phone, multi tool and dip using the 556 insert. I like keeping my keys and wallet on my person, plenty of room in the sack. Great to use for hikes as well as on the range. It will accompany me on every hike from now on.

Mk 3 Micro Fight
Written by Lindy on Mar 14th 2018

Addresses the only downside of the Bank Robber, having room for patches.

Written by John on Mar 13th 2018

So I'm not a high speed operator or anything, I'm just a civilian paramedic/armed citizen who used to be a national guard guy, and I think this kit is awesome. It's the kind of gear I wish I had while I was deployed. What made this worth getting for me is the fact that it's modular and fits comfortably under my ruck. Because of this I can use it to: 1. Carry essentials like maps, gps, and first aid up front when I'm hiking or volunteering with SAR. I can even fit my glock 17 in the front pocket, though it's not super quick to retrieve. I use a maxpedition Velcro pouch to put an ifak in the main pocket in this format. 2. Keep rifle mags, pistol mags, ifak, eye pro, ear pro, gloves, and extra batteries in one rig for range days. 3. Sit in my basement filled with nostalgia over the fact that I order mine in m81 and that's what I wore for half my short contract.

mk 3
Written by chris on Mar 1st 2018

This systems is clearly well thought out and the modularity is amazing. I've used it in conjunction with my mayflower apc and issued gen 3 iotv with swift clips. I also bought the 5.56 rifle mag insert which has perfect retention (very secure but not difficult to draw.) The one potential drawback which is easy to see in the picture is the space between magazines is nill which prevents a complete purchase on the mag in the draw. That being said if you're into doing fast, sexy mag changes for your insta this might not be perfect for you. I find for duty use it's perfect especially considering how surprisingly easy it is to re index a mag.

Great chest rig
Written by Frank on Feb 27th 2018

I love this chest rig the moment it came in the mail. I really like the high quality materials used to produce this product. Also love the fast shipping. Keep it up Spiritus!

Written by Britton Fuller on Feb 23rd 2018

You guys have great quality products and really great customer service. Its good to see your company doing well. Microfight rig set up multicam tropic killin it

Fully Modular
Written by Brandt on Feb 17th 2018

Being someone who is not MIL/LEO, take what i have to say with a grain of salt, with that being said; I am someone who understands materials and understands what quality is when it comes to components and materials used in production of items used for hard and lasting use. The MK3(III) chassis is of high construction quality and the stitch work is very accurate and precise with the angles and surface area of the materials used in the overall construction. The velcro both hook and loop are very tight in weave and they seem to have been sourced from a good manufactuer of H/L product. They appear to be able to have many rips and pull life in them without straightening out over extended use or time use, which can happen with lower end quality H/L products. The plastic buckles provided with the MK3(III) are of a good mold and are molded with good "plastic-polymer" material that can withstand very low/freezing temperatures and also withstand very hot and humid temperatures. they are an un-smoothed and low-coarse in nature (much like a p-mag) that will allow great grip retention if the user had to unbuckle or re-buckle need be. I believe that the buckles really fi the nature of the product and add another point to the reasoning of "modularity" because it can be used in a vast and wide range of environments. The overall package and size of the MK3(III) is user configurable and can be set up with other items sold by Spiritus Systems but as it stands alone it is small enough to be low-vis under a coat or jacket, but still large enough to be used as an "assault" rig or a recon* rig. As a civilian with Life, Liberty, and Independence in mind, this system makes me feel very lightweight as well as being fully prepared for any situation. 5/5 for an overall rating for the MK3(III) Chassis in all aspects: 1.Construction 2.Modularity and 3.Comfort(does it irritate the skin/user etc)

Full Feature Adapatable Rig
Written by Colby on Feb 11th 2018

The simplicity and modularity of this system(Chassis, Fat Straps, Back Strap, Inserts, Full and Half Flaps, Expander Wings, and SACK) is incredible. I purchased the Chassis, Inserts, and Flaps in Multicam Alpine initially as a placard set up for field problems in the north. Shortly after receiving the initial set up I purchased the Fat Staps, Back Strap, Expander Wings, and SACK. When we don over whites I detach the placard, attach the Fat Staps and Back Strap and wear the rig over my over whites. Scaling and tailoring the rig to mission sets and positions is quick and easy and the rig seems to be well constructed out of quality materials. Regarding the Rigs’s performace/capacity. The adaptability of the rig makes it easy for me to carryeverythi g from my 148/152s, IZLID, map/imagery, LRF, strobe, GPS, chemlights, IFAK and 3-5 magazines over over whites as requirements dictate or just wear the chassis as a 3 magazine placard.

Item received !
Written by Pilotelle on Feb 7th 2018


Written by Rory S. on Jan 26th 2018

I absolutely love this chest rig. It's the right size for a smaller low profile system. Has top tier quality in the stitching, materials and overall craftsmanship. Easy to set up to your preferred way. I bought this product because I saw many uses for it, ranging from hiking to defensive/offensive operations. Keep up the awesome work! 10/10

Micro Fight Chassis MK3
Written by Garrett S on Jan 23rd 2018

The quality and expandability of this system is exactly what I was looking for in a chest rig system. It fits perfect, doesn't move when using it and puts your equipment at the perfect level for quick deployment. I would highly recommend this to anyone who is looking for a fighting system.

very happy
Written by Vinny Fulgieri on Jan 20th 2018

so this probably is one of the best rigs you're going to find out there for the sole reason of adaptability. you're not locked in to anything with this set up. set it up how youd like and drop it in to any plate carrier or run it solely as a chest rig its awesome. DO NOT HESITATE TO BUY THIS

Written by Mark W. on Dec 22nd 2017

Received my rig (and all the other components) last week and put it all together. I'm extremely satisfied with the quality and function of everything. I have my rig set up with the triple AR mag pouch, and the double pistol mag and half flap. The versatility of their design is an absolute game changer. I went out to the range the other day and this rig fits so well and it so low profile at times I forgot I even had it on. For anybody looking chest rig, look no further, this it it.

MK3 Rig
Written by Charles on Dec 14th 2017

Now that I have my rig I love it, fits great, and I love that it's in the Woodland pattern.

Review for Micro Fight Chassis MK3
Written by Thomas on Dec 2nd 2017

Best low profile chest rig out there hands down.

Written by Ted on Nov 17th 2017

Super low profile. Well made. Only thing is read the description, I didn't read and you need to get the inserts to actually use it. Completely my fault.

High Speed
Written by Hayden on Oct 25th 2017

Bought the Multicam Tropic version and was very impressed. I have several Haley Strategic D3CR’s which are really good rigs to run but this blows them out of the water. The versatility of this platform is second to none, it’s lightweight and allows for ease of movement. I would highly recommend this to anyone

Mk 3 Review
Written by Stash on Aug 13th 2017

I have 2 of these Chassis now. By far my favorite chest rigs and pieces of gear I own. I have gone from a knock-off RRV rig, to a super minimalist hypalon skeleton chest rig with pouches attached, to this. There is no comparison. It's low-profile, yet it can carry whatever I need it to, and more than I should really want to carry on a chest rig in some instances. Changing loadouts is worlds easier and faster than re-threading molle pouches. Rides well, maybe a tad low but I'm on the short side with the fat straps. No purchase ragrets whatsoever.

Awesome Chest Rig!
Written by Mathew Vnuk on Aug 7th 2017

If you're looking for affordable and quality gear I'd highly recommend Spiritus Systems Micro Fight Rig! It's meticulously built and designed, it's versatility is also top notch. No matter your load out you'll be able to carry all the necessities with ease of movement and accessibility. As compared to other companies, they can't match this Rig as most are built to carry specific load outs without the ability to swap out for other gear. With a few minutes you can completely create multiple variations of this rig to suit your needs. No mission is ever the same, make sure your gear is ready to adapt.

Top Notch
Written by RogueWeasel on May 1st 2017

Best rig I've run yet, access to everything. I need while keeping a low profile. Great job guys.

Written by Scott on Apr 30th 2017

Dope, small, compact, durable, completely customizable, lightweight. This thing is awesome!

The Best. Period.
Written by Ben on Feb 21st 2017

Through my business in the firearms industry I get to handle a lot of nylon gear (Chest rigs, belts, pouches, plate carriers, etc.) and the Micro Fight is one of the best nylon products to spend your hard earned money on. The Micro Fight Rig is just such a simple well thought out design. The endless modularity and load out options are really quite incredible for how small it is. The craftsmanship takes the design into the hall of fame in my opinion. If your a serious shooter, LEO, and/or Mil I would highly recommend this piece of kit. -Ben Wise Men Company

Review of Micro Chest Rig
Written by Justin Wilbur on Jan 3rd 2017

I'll just review the whole rig. Considering I bought all of the Spiritus. I love the simplicity and ease of the system. Great rig and amazingly versatile.

Quality product that offers lots of flexibility
Written by McKay on Nov 17th 2016

I wanted a chestrig that I could reconfigure depending on what I'm doing and what I want to carry. The short answer is this does exactly what I wanted it to, and I'm very impressed. I bought the Micro fight with the straps and a few of the inserts. This chest rig allows me to carry 3 AR mags, 2 Glock mags, and still has room for my Glock 19, or my rangefinder, or whatever else I decide to carry. I like that I can easily switch things around and carry everything I need for my coyote hunts in a quiet and convenient way too, even though the rig wasn't necessarily designed for that. But that's why I love this rig so much. It allows me control to add or take away from my loadout, and reconfigure it as I please. I was a little uncertain of how well the mags would be retained, but after I've used it, I am not worried about mags accidentally coming loose. My initial impressions of the quality are good. It seems durable and it's very lightweight. As for comfort, carrying weight around is never comfortable, but I don't see any way this rig can be improved in that area. It's as comfortable as I can imagine a chest rig can be. I'd recommend this product to anyone who wants the flexibility to configure their loadout in an assortment of diffferent ways, or anyone looking for a simple and effective way to carry your gear. Also worth noting, my experience with their customer service has been very good. my questions were answered very promptly through direct message on Instagram, and my order was processed and shipped within an hour or two of when I submitted payment.