Shop › SCO PISTON 1/2"X28 XL SCO PISTON 1/2"X28 XL $75.65 SilencerCo Extended Piston, 1/2 x 28 RH, Fits Osprey/Octane AC59 Quantity: Add To Cart Added! SilencerCo Extended Piston, 1/2 x 28 RH, Fits Osprey/Octane AC59