Micro Fight Chassis MK4

Height 5.00
Width 9.00
Depth 1.00
Color None Selected Required


The Micro Fight Chest Rig Mk4 is designed to be extremely efficient, modular, and lightweight. The Micro Fight works seamlessly with our accessories suite, which offers nearly endless configurations. The Micro Fight features soft loop Velcro in both pockets to 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 5” x 9” field of hard loop Velcro on the back of the rig allows for solid integration with accessories, such as the SACK Pouch or Expander Wings. The larger Velcro field also allows a solid integration onto plate carriers, such as the LV119. In addition to the larger Velcro field, the MK 4 also allows for sub load integration of a tourniquet utilizing the two integrated grommets and our Universal Retention Kit. 


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, 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 48 ratings)
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Micro flight
Written by Casey Edwards on Feb 21st 2020

Great gear nice and compact Would like to see something on the sides though like that is on the bank robbers rig for attaching tourniquets or whatever but other than that it’s great

Micro Fight Mk4 Chasis
Written by Curly Bill on Feb 21st 2020

The Micro Fight is a slim, yet smooth and functional chest rig or plate carrier placard. Despite its small size, rifle and pistol mags slide in and out without binding, and are held in securely. On a plate carrier, not having to configure different pouches and pockets on MOLLE for different roles and load outs is a huge advantage of the placard system, just unfasten the clips and peel off from the Velcro and replace with another placard, and the micro fight excels at this. As a budget consideration, the ability to configure the micro fight for pistols mag, sub-gun mags, M4 mags, 7.62 mags, or any combination therein, and have room for tools, snacks, med kits, etc. this makes the system economical as well. I dig it!

Micro Fight MK4
Written by DEMPSEY on Feb 20th 2020

Chassis works great on my plate carrier, and beats the hell out of trying to adjust MOLLE pouches for different jobs. Also easy to remove/attach the chassis to wear the carrier under a cover shirt during a surveillance with an anticipated take down. I would like a two 5.56 mag holder option to carry two rifle mags and two pistol mags in the same pocket of the chassis.

Amazing, Low Profile, and Extremely Modular
Written by Hardy Adams III on Feb 19th 2020

Bought one of these to fit on a Ferro Concepts Slickster plate carrier and bought Spiritus's Fat Straps to make into a chest rig. this Chassis system is extremely durable and modular. One of the best parts about the whole system is you can pick and choose what you want with the kit vs having to buy stuff you do not need. I absolutely love this Chassis system and have recommenced it to plenty of other shooters.

Written by Billy on Feb 19th 2020

Wish I would have gotten one years ago. I use it for a mixture of 40mm/rifle mags/explosive breaching tools and cannot say enough good things about it. Being able to customize it in a multitude of ways makes it indespensible. A lot of thought when into making it so that you can make it work for you. On top of that they ship it seemingly within minutes of getting your order so that's awesome too.

I own 3 of these
Written by Cody Fletcher on Feb 17th 2020

Not only is spiritus products top quality, ingenuity and versatility , but the service and support is top notch as well. I own 3 mk4 chest rigs and I own at least every type of insert. Best gear, best service, best company period!

MK4- MC Arid
Written by Sean on Feb 12th 2020

The tits, design is great to run double stacked or in a slicker profile. Golden standard of versatility. Adds a minimum of 15% operator points while clearing your house in silkies, increased draw speed of 10% easily, also increases girth and stamina.

Best Rig Period
Written by Ryan on Feb 5th 2020

This is the hands-down the best rig I’ve ever used, it’s super configurable on the fly and can handle whatever job you’ve got for it with plenty of room for the essentials. I wouldn’t want to run anything else after using this piece of kit - unless the MK5 is ready!

Chest Rig
Written by Dustin Lavergne on Jan 22nd 2020

With this being the 2nd plate carrier setup from Spiritus Systems that I use daily....it was no doubt that I was going to snag their chest rig. Most modular system out there. Being able to configure the rig in soooo many different ways helps me tremendously with my day to day ops because they vary from one to the other. Thanks Ben and the crew at Spiritus. You’ve got yourself a lifelong customer!

Great Product
Written by Christian Larkins on Jan 21st 2020

Perfect product that has amazing modularity , anything you can think of you can do with what is available from spiritus

Best chest rig
Written by Rookie on Jan 20th 2020

Best chest rig I've ever run. Compact, no-nonsense piece of kit. Super versatile and modular. Highly recommend.

Great piece of kit!
Written by Chad on Jan 12th 2020

I order this product based on the compact design and modularity. I love that it can be configured to meet the mission. It's very well made, I couldn't find one thing to nitpick. I have it mounted on a velocity systems scarab LT and it works better than expected. I do reccomend also purchasing the AXLadvanced front zip insert along with the chassis. Overall, I'm very please with this product!

Incredible Chassis
Written by Nick on Jan 9th 2020

I have owned a few chest rigs and utilized most of the ones I have purchased down range, all with their own pros and cons, but I have not found a better quality or more modular chest rig on the market than Spiritus Systems. Specifically, the Micro Fight rig. I can honestly say I have found a rig I have zero complaints with as I am a firm believer in “you get what you pay for.” Being able to switch the rig around in literally seconds to suit the needs of an operation is incredible. After multiple switches and uses the rig still maintains its form and integrity with very little wear and tear. I cannot say enough good things about this company or this product.

Top notch
Written by Michael Tater on Jan 6th 2020

Love the color, the mags fit nice and tight with the insert! Couldn’t be happier with this product!

Written by Kyle Savage on Dec 20th 2019

Very modular and versatile.

Mirco Fight MK4
Written by Chaz C on Dec 19th 2019

This thing is legit. I use it on the LV 119 carrier and it just works. SUPER modular, easy to use inserts, and having 2 pockets is a nice touch!

Written by Jr on Dec 18th 2019

I use the front pouch for documents, comms cards, SI lists, maps and protractors, etc.. there is a good amount of room. Side note.. I wish I would have bought two half flaps, rather than the long one to cover the front pouch. That way I could change my set-up to half open or fully closed based on mission essentials.

Solid piece of kit
Written by Nick on Dec 9th 2019

Very good chest rig, not too cumbersome, just what I need. Would definitely recommend just due to the scalability of the platform alone.

Written by Jaime Trejo Jr. on Dec 6th 2019

Feels great and the stitching looks well done as well. Looks very well made and I’m looking forward to using this rig on the range very soon.

Mk4 Rig
Written by Joseph A on Dec 2nd 2019

Very nice system! It’s very versatile and modular which for me is amazing since it works well as a range rig and also a SHTF situation. Love everything about it!

If you like Modularity, this is your pick.
Written by Alexander Das on Nov 13th 2019

Just that simple, folks. If you want a chest rig/carrier placard that you can modify to be the way you want it, look no further. Medical, Rifle Mags, Pistol Mags, Multitool, Notebook, Backup Burrito. Whatever you want to throw in here, you can modify the Chassis to accommodate it.

HQ practicality.
Written by Edward Yost on Nov 5th 2019

Useful and expadability are two major pros. Cons maybe the small baseline capacity if you run AK. Though if you're creative with this and the Advanced LV119 Cummerbund you can end up with 4-5 mags so just takes some working around. Modularity is high. So is the stitching and build quality. Go buy one.

Good stuff
Written by Brandon Foust on Nov 4th 2019

Been running the chassis on my plate carrier for about 6 months, comfortable and gets the job done like a good chassis should

Micro Fight Chassis
Written by William Rodgers on Oct 4th 2019

I got the entire system to replace the factory m4 chest rig on my issues Plate Carrier. The old one is much bigger and bulkier, none of the pouches are laid out in an ideal pattern, half the pouches are useless for our mission and are repurposed for other gear but even thenthey suck. The micro fight fixed all that! Everything is lighter and slimmer and tight against the body. No more dead space, no sloppy nylon flopping around and not a single wasted pouch. Everything is exactly where and how I want it. The ability to move everything and not have multiple rigs is what makes this the last system you’ll need.

Micro chest rig
Written by Nick Mclaughlin on Oct 3rd 2019

This is my second chest rig from Spiritus and, as usual, it’s good to go. Got the MC black and Ranger Green slicksters, coupled with all Spiritus goods and damn does it work!

Micro Fight Chassis MK4
Written by anthony m lowery on Sep 30th 2019

I too am a LARP enthusiast, I operate all over the house, and occasionally make people feel uncomfortable at the range. This chest rig is legit, it will fit tendies of various sizes and a few magazines. One a serious note, the quality is there. This micro handles everything that this civ needs it to. Some medical, two pistol mags, three ar mags, a light and a multitool. The removable cover for the back is a great touch.

Micro Fight in Multicam
Written by Chris J. on Sep 27th 2019

I've had this for a few weeks now and have LARP'd around the house with it as a chest rig and placard on a Ferro Slickster. It has a great feel and I love the modularity of it. I wish they would make a retention insert for it but the current inserts work well.

Great Product
Written by Gian C Abalos on Sep 11th 2019

Well worth the money.

Solid kit for a loadout
Written by J MASTRONARDI on Sep 11th 2019

I recently purchased the whole package. Chassis, straps, s.a.c.k., expander wings, rifle and sub gun inserts, and a full flap. Solid construction. Solid fit. Pieces mesh together perfectly. Easily worn with our without plate carrier. Before you buy from someone else, check to see if Spiritus has what you're looking for. Would definitely buy again.

Just Awesome
Written by Adam on Sep 10th 2019

So this is awesome much better than I expected. You will not be disappointed.

Micro fight
Written by Nick on Sep 7th 2019

Truly adaptable. I’ve owned many chest rigs and been issued many LBV/FLC rigs, and this really is my favorite. I’ve owned Haley strategic, TAG, tactical tailor, BDS tactical and Blackhawk!, and none give you the flexibility that this system gives you. It’s compact, light and doesn’t have a bulky feeling in the straps like others do.

Perfect combo with hsp flatpack
Written by C on Aug 28th 2019

Added to my hsp flatpack to carry my tank. Have the 5.56 mirco flight rifle insert and pistol mag. Fit snug and minimal if any bounce when running. Perfect addition to any set up.

It works for us LEO guys too!
Written by RKB on Jul 22nd 2019

If you’re a plain clothes street cop who wears regular body armor and not a plate carrier wearing operator, this works for you as well! Sticks right onto my low pro body Armour and all my gear is where I need it. No straps necessary.

Perfect rig
Written by Sean on Jul 6th 2019

I’m relatively new to the black rifle, but needed a rig for rifle classes I’m taking, and this is perfect. I know nothing about chest rigs but someone from AR15.Com posted a pic of their set up from Spiritus. Put everything together in less than 15 minutes. This rig is versatile as your imagination. I went with the full flap, putting gloves, a TQ and quickclot in the front pouch. I found it easier to put the mag pouch in the main pouch first...

Micro Fight
Written by Cocomo on Jun 24th 2019

I recently purchased a micro fight chest rig, fatboy starps, back strap, 5.56 insert, and full pocket flap. Fast shipping, fast delivery. Great customer service, i made (2) orders by mistake, and customer service took care of everything right away via messages thru their message board. Now the product. The only thing that kept me ordering this long ago was i was concerned about the cost vs quality ratio. Upon purchasing it im happy to say its money well spent. The quality and durability are unmatched. I am so happy with spiritus systems and the way their product complemented my kit. Some people say they dont like how you have to buy all the individual pieces, but that is a way to only buy the components that you want/need. I would highly recommend spiritus systems for anyone who wants a quality chest rig, custom built by you to soot your needs.

Singing the virtues
Written by Aaron on Jun 23rd 2019

Just another review singing the virtues of the system. Shipping is superfast and the ability to build the way the end user wants is paramount. Worth the cost. Velcro and stitching is all solid. Swiftly begins to contort to wearer. Wore it around the house a few nights to wifes chagrin before got first usage outdoors. Ditching the padded belt for this after I finish with components and addons. This entire system feels super light in comparison to most belt setups

Spiritus Micro Fight Chest Rig
Written by Tyler Massey on May 30th 2019

To say I’m impressed is an understatement. I’m the kind of person that studies a lot before I spend my money on something. I studied many chest rigs, I wanted something minimal. I went back and forth between this and an AO Chest Rig. I finally pulled the trigger and bought this. It is amazing. It’s minimalist, and very modular. Not only can it be worn as a chest rig, but it can be worn as a bandolier if needed with the back straps. Impressive. Bravo guys.

Great piece of gear
Written by Jeremey Merrill on May 27th 2019

I love the MK4 for several reasons. It is a very capable system while still being a minimalist type design. With a larger setup it's very easy to overload yourself just because you have the room. With this rig it helps keep you to the essentials. I also love how modular it is. Your not tied down to what is out of the package but you have a few options to configure it the way you want.

Micro has a lot of fight!
Written by Michael Hart on May 25th 2019

Innovative, compact design holds everything you need in place with great retention. Easy to change up the load out without having to unweave and reinstall pals pouches. Excellent piece of kit for your plate carrier for what ever mission you have! If you are LE and carry a taser, may I recommend a Zero 9 taser holster. Slap some Velcro on the outside of it and install it in your micro fight chest rig. Perfect fit!

Best rig on the market
Written by Ethan Filetti on May 10th 2019

Yes, getting the rig with all the trimmings might be pricey. I would say that is the only con to choosing this. But you get what you paid for. The modularity is out of this world, I'm blown away. That, and the fact it all comes in MC Tropic

Micro Fight Chassis mk4
Written by Josiah on May 4th 2019

Great quality. This product is by far one of the best micro rigs on the market. I'm really impressed with it and would recommend it to anyone that's in the market for a micro rig setup. I'm currently running it through hell and its holding up great.

Written by Kris on Apr 26th 2019

I've had several microfights over the last few years and now they are all set up for different dedicated purposes (carbine, subgun, etc) and what i love the most is the adaptability. Whatever theater i'm working in, or stateside, I can tailor the microlight to exactly what I need and between running it as a placard or standalone chest rig it finds a purpose perfectly in every task I need on the body storage or for a quick access grab and go setup.

Usage on Conventional Army PC
Written by Phil on Apr 16th 2019

I've always had an admin pouch slapped onto a triple mag pouch on the front of my Army-issued plate carrier/IOTV. This little beauty combines both of those into one small system. To mount it I just took the side buckles off, tucked the top ones behind it, and zip-tied the side loops right to my MOLLE. Works like a charm and doesn't move or bounce around. Even got my commander to order one ;)

Best chest rig on the market.
Written by David on Apr 1st 2019

I have experience with haley strategic chest rigs and many other light weight molly chest rigs and I have to say by far the spiritus chest rig is my favorite.

Written by Austin on Mar 18th 2019

I was deciding between Spiritus and Ferro and due to cost went with Ferro first.... Once receiving their rig I knew I made a huge mistake and was nothing but frustrated with it, I returned it and invested in the Spiritus and could not be happier with spending a little extra coin. The design behind this rig is superior to anything else I have used. You have all the customization options you could want and I love that it isn't massive. Your rig should not be cumbersome and constantly in the way, and this couldn't do a better job of having a small footprint all while having everything I need and nothing I don't. The fat straps are great and distribute the weight well, they don't cut into your neck, or fall off - they stay put. The stitching and construction is rock solid, this thing is not falling apart anytime soon. The velcro is not cheap - that stuff holds on really tight to whatever you put there, whether it be the insert mag pouches or something on the outside. Stop thinking about it and invest in the Spiritus Rig - you wont regret it.

Microfight Chassis
Written by Tyler on Mar 11th 2019

Spiritus is a great company with great gear and better customer service. The only con of note is the thickness of the chassis when fully loaded on a plate carrier. With that being said if you don't over load your gear and shove a bunch of nonessential gear into it the chassis has the perfect profile. That's it. It's not even a true con. If you don't like Spiritus's elastic retention system get a kydex insert. There is no reason to not run this as a standalone system or a placard.

Initial Impressions
Written by Ramiro on Feb 24th 2019

My initial impressions upon recieving this rig are, "this thing is light and tiny". I have a Haley D3CRX, which comes with 4 rifle and 4 pistol mag pouches, with 2 general purpose pouches. Throughout my ownership of the HSP rig, i found that i never needed the amount of mags the rig could hold. I found that I'd use the rifle mags and general pouches for storage but never the pistol since i wear a duty belt. Full disclosure, I'm a civilian, this gets used for training, and working armed at events. Now for the MK4, i have yet to use it. However, I am impressed with the construction and selection in materials. It really contributes to how light weight this rig is. Without knowing the exact makeup, the rig appears to be made from 500D cordura (which is strong enough for 99% of applications without the weight). It has double and quadruple stitching in high stress areas. The buckles also appear to be high strength and it's really hard to see but appear to be box stitched to the rig. I can tell just looking over the rig, that high strength and aesthetics were very important while maintaining low weight. The order in assembly was clearly thought out as it actually conceals the amount of threads on this rig. Needless to say, I am impressed by Spiritus Systems. This is not my first piece of kit, but it is my first piece from them. I look forward to trying more products from them in the future! The setup ordered is: MK4 MC Black, double pistol, triple rifle, tq holder. Still need to add: Full flap, wings for radio, maybe another double pistol.

Awesome rig
Written by Nolki on Feb 23rd 2019

Very cool and comfortable rigs.