The MkGs BANSHEE in .40 S&W platform lower receivers are designed to accept small frame 9mm/.40 S&W Glock-pattern magazines. Magazines for either caliber must match the caliber the upper group being used is chambered in. The MkGs features EML handguards, full length M-LOK slots on both sides and the bottom of the handguard as well as M-LOK between the top picatinny rail sections; last round bolt hold open; Radial Delayed Blowback operating system; full kit of ZEROED parts including: pistol grip, drop-in trigger, 60/90 degree ambi safety, linear compensator 45 ACP, AR15- ambi charging handle, bolt catch and polymer dust cover. Includes Glock 22rd magazine.