The X20 S2 Suppressor's operating system has been thoroughly tried and tested for toughness and durability, and has been chosen for its long-lasting reliability and ballistic precision. The cocking action is accomplished with a break-open barrel that relies on a simple spring and piston pairing. Stoeger Airguns neither require, nor rely on expensive CO2 cartridges or pre-compressed air bottles to operate. This makes them both economical to shoot and dependable in function. The latest innovation from Stoeger Airguns is the X20 S2 Suppressor. Employing Air Flow Control (AFC) techhnology, the Dual-Stage Noise Reduction System, designed by world-renowned silencer designers Humbert CTTS, makes it the quietest airgun in its class.