The APS is a straight-blowback, select-fire, magazine-fed machine pistol. The weapon is fed through 20-round double-stack staggered-feed detachable steel box magazines. The APS shares features with the Makarov service pistol, such as a heel-mounted magazine release, slide-mounted safety lever, and field-strip procedure. The rear sight is adjustable from 25, 50, 100 to 200 meters through an eccentric rotating drum-dial. The serrated front sight may be drifted for windage. The slide features a textured strip on top to reduce aim-disturbing glare. The chrome-lined barrel serves as the recoil spring guide. The slide stop lever also acts as an ejector blade. The trigger guard pivots down for stripping and detents in position through a spring-loaded plunger. The checkered or serrated grips' panels are made from wood (early models), reddish-brown bakelite or black plastic.