SPIDER4D RTP SLOT This secondary chamber is split in half, with the upper half being a simple expansion chamber for the first stage while the bottom half has a port from after (i.e., closer to the muzzle) the primary baffles to another mesh baffle system. The suppressor is a two-stage suppressor: it has a baffle system in line with the barrel, and a secondary chamber under the barrel. Uniquely for a blowback pistol, it features a rotating bolt with locking lugs; this feature is to allow for the selection of semi-automatic or manual operation.|System Of A Down