Built SR25 box by Dan Blomquist. For A&K and Classic Army. Sturdy as all heck. Will last longer than you. Semi locked. Shoots 475 fps w/.20s. What's inside: Lonex compression parts Gate Titan mosfet Retro Arms 8mm bushings Guarder spring SHS piston Retro Arms trigger SHS gears ASG Infinite Torque 28 TPA motor Free shipping!