Spiritus Systems Micro Fight Chassis Mk4 | Modular Chest Rig Platform

Lightweight Foundation for a Fully Custom Tactical Loadout.

The Spiritus Systems Micro Fight Chassis Mk4 is a modular chest rig platform designed to serve as the core of a lightweight tactical loadout. Built for adaptability, the Mk4 works as a standalone chest rig or as a placard mounted to a plate carrier, making it one of the most versatile pieces of gear in the Spiritus Systems ecosystem.

Designed around the Spiritus modular system, the Mk4 integrates seamlessly with Spiritus inserts, flaps, wings, and accessories, allowing users to build anything from a slick low-profile setup to a fully equipped combat chest rig.

The chassis features soft loop Velcro lining inside both compartments, allowing precise placement of magazine inserts, radio holders, admin tools, or other mission-specific accessories. This layout supports up to six 5.56 magazines or four 7.62 magazines, along with mixed rifle and pistol configurations depending on your insert setup.

On the rear, a 5 inch by 9 inch hard loop Velcro panel allows direct integration with plate carriers, back panels, Expander Wings, and SACK pouches. The Mk4 is commonly paired with carriers like the Spiritus Systems LV119, turning the chassis into a modular placard system.

Integrated grommets allow tourniquet mounting when used with the optional Universal Retention Kit, providing rapid access to life-saving medical gear without taking up internal space.

If you are searching for a Spiritus Systems chest rig, modular chest rig platform, Micro Fight placard, or lightweight tactical chest rig system, the Micro Fight Chassis Mk4 provides a proven platform trusted by military, law enforcement, and prepared civilians alike.

Why We Love the Spiritus Systems Micro Fight Chassis Mk4:

It is one of the most modular chest rig platforms available. The Mk4 acts as a blank canvas that lets you build your exact loadout using the Spiritus ecosystem.

Whether you are running a minimalist setup or a fully configured combat rig, the Mk4 scales with your mission.

Key Features of the Spiritus Systems Micro Fight Chassis Mk4:

• Modular chest rig platform compatible with the Spiritus Systems ecosystem

• Works as a standalone chest rig or plate carrier placard

• Soft loop Velcro interior for customizable insert placement

• Rear 5 inch x 9 inch hard loop Velcro panel for carrier mounting

• Supports six 5.56 magazines or four 7.62 magazines depending on insert configuration

• Integrated tourniquet mounting grommets

• Ultra low profile design ideal for low visibility setups

• Lightweight yet rugged construction for professional use

• Made in the USA

Important Note

This listing includes the Micro Fight Chassis Mk4 only.

Shoulder straps, back strap, magazine inserts, flaps, wings, and other accessories are sold separately and required to run the chassis as a complete chest rig.