HK Army Performance Series MID Pressure 450-550psi, MP5 Piston

Restore your regulator's factory performance or swap your output pressure with this drop-in HK Army MP5 Piston. Designed specifically for Performance Series regulators, it lets you preset your output to a consistent 450–550 psi to match your gun's requirements. Instead of a standard coil spring, this unit uses a Belleville Shim Stack, compact disc springs that deliver massive force in a small space, ensuring a rapid air recovery rate between shots.

The stack is built on a heavy-duty brass piston and comes with high-quality O-rings pre-installed for a leak-free seal right out of the box. Installation is straightforward: the entire shim and piston unit pulls out as one piece, so you can swap it in minutes and get back on the field. Just remember to completely degas your tank before opening the regulator to avoid injury.

Features:

• 450–550 PSI preset output pressure
• Belleville shim stack design
• Quick-swap internal assembly
• Durable brass piston construction
• Leak-free O-ring seals included
• Consistent output pressure restoration
• Compatible with Performance Series regulators
• Lightweight and compact profile