The Stoeger X20S Suppressor Air Rifle offers the Dual-Stage Noise Reduction SystemTM with Air Flow Control (AFC) technology, designed by world-renowned silencer designers Humbert CTTS. Others use only sound-dampening baffles, so the internal air-regulator ring helps it reduce noise better than any other pellet gun on the market. This ring has 4 decompression holes that bleed off most of the compressed air before the pellet even enters the baffles. The remaining compressed air dissipates throughout the baffles, further reducing noise.
When tested in a certified sound chamber at an independent testing facility, the Suppressor was as much as 7.05 decibels quieter than the competition's "quiet" air guns. Meanwhile, it not only achieved the highest average velocity among those tested, but also the most consistent.