New from TTI Airsoft is this High Pressure Piston for the VSR and clone rifles.

It's been made from lightweight alloy and stainless steel for durability, features two Delrin bands for less resistance and a pair of o-rings up front. The main o-ring is substantially larger than the other and is designed to do the majority of the work, with the secondary picking up any pressure that manages to leak past.

A rubber pad on the end finishes the piston and helps reduce the impact shock to the Cylinder Head.