The 51P pistol features a classic style polymer handguard with an 8.5" bull barrel. The precision-welded top rail allows the addition of your favorite optic or use the traditional iron sights (included). The end cap is compatible with M4 buffer tubes or the included swivel end adapter. Features: Classic style polymer handguard 8.5" Bull barrel 7.5" top rail for quick optic mounting M4 buffer tube compatible end cap with swivel end adapter Paddle style magazine release