Geissele Automatics Trigger, Super Dynamic 3 Gun 05-166 The Geissele Super Dynamic 3 Gun (SD-3G) Trigger is based on the S3G Trigger. Like the S3G" the SD-3G has a shortened pull length and a lightning-quick reset to give it a unique" hybrid trigger pull that is a cross between a traditional two-stage and single-stage trigger while still retaining the safety and robustness of a two-stage combat trigger. The SD-3G's flat trigger bow further enhances the trigger's performance by reducing the perceived pull weight and improving the trigger's tactile feedback to the operator making it ideally suited for 3 Gun competition shooting.