This is a semi-automatic-only version of Geissele Automatics’s Super Select-Fire trigger. The large pin dimension is 0.169 inches, whereas the standard pin dimension is 0.155 inches. The SSA Large Pin is a 4.5lb. non-adjustable combat trigger that is a precision two-stage trigger and allows precise and accurate trigger control. The SSA’s two-stage design allows the trigger to be light enough for accurate and precise shots, but forgiving enough for CQB. The SSA is safety certified by Crane Naval Surface Warfare Center. It is recommended for demanding applications such as Law Enforcement use, Close Quarters Battle (CQB) and mid-range carbine work.