SIG Air M18 Green Gas Airsoft Pistol Uses 6mm airsoft BBs Semi-auto Full blowback action Metal slide Authentic Coyote Tan slide and frame 21-round metal magazine Field strippable Max. velocity: 320 FPS Ambidextrous thumb safety and slide lock Textured grip Fixed front and rear white dot sights Reflex sight mounting plate Under-muzzle Picatinny accessory rail Uses flush-mount green gas magazine Overall length: 7.7" Weight: 24 oz.