The Geissele Super Dynamic-Enhanced (SD-E) Trigger featuring an exclusive flat trigger bow, is a finely-tuned two stage trigger providing enhanced trigger control and weapon accuracy while maintaining the robustness and reliability of our combat-proven two-stage trigger. Type: 2 Stage 1st Stage Weight: 2.3lbs. 2nd Stage Weight: 1.2lbs. Total Pull Weight: 3.5lbs. Adjustable: No Recommended Use: Target Shooting, Precision Shooting Pin Size: Mil-Spec All weights are approximates. Please note, our triggers are designed for mil-spec AR15/M4 carbine rifles. Our AR15 triggers are not compatible with the Sig MPX/MCX weapons. The SSA-MPX trigger will be available in 2017. Please call 610-272-2060 for details. The Geissele Super Dynamic-Enhanced (SD-E) Trigger featuring an exclusive flat trigger bow.