Timney trigger ar-15 3lb pull solid large pin FEATURES:-Fits all Military Spec Built Lowers, AR-556, Mossberg MMR Hunter, Mossberg MMR Tactical, Mossberg MMR Tactical w/sights, SR-556, SR-556 Carbine, SR-556 VT, SR-556E-3 lb pull weight-Large pin-Easy installation w/ no adjustments necessary-100% true drop-in trigger-No pin rotation Other Features: For pre-2005 colt ar-15's large (.168-.174) trigger pin large pin model (.168-.174) 3 lbs pull non adjustable solid trigger works only with older colt ar-15 rifles (pre-2005)