This piston head feature:
– Viton Oring with a ventilated design.
– No airbrake, short, medium & long airbrake options (for 4.00 mm internal nozzle – for original SRS & TAC-41 cylinder head
– POM piston ring
– NBR 80° Oring damper
– Stainless steel CNC construction, for additional piston mass (from 30.2 up to 31.7 grams, instead of 7.6 grams for the original piston head)
An airbrake is cutting the air flow before the piston hits the bottom of the cylinder, creating an air damper that will reduce the impact noise, possibly at the cost of muzzle energy reduction.