The Super APC Trigger from Geissele offers a boost in trigger performance over the standard trigger found in the B& T APC9 and APC45 firearms. The while the single stage trigger is not adjustable, it ships with a light and heavy spring allowing you to choose between a 2.75 lb. or 4 lb. trigger pull. Geissele Automatics Geissele Super APC9/45 Trigger BT-SuperAPC