RIFLE: BUSHMASTER FIREARMS MODEL XM15-E2S - RIFLE, SERIAL NUMBER BK5001918, BLACK (MATTE), CASE NOT INCLUDED, SEMI - AUTOMATIC, 5.56MM, 16.5" Notes: The Bushmaster XM15-E2S is a semi-automatic rifle chambered in 5.56mm, featuring a black matte finish and a 16.5-inch barrel. This rifle offers a familiar sporting rifle design and versatile configuration. The case is not included.