TheTru-Fire Synapse thumb release with true double-sear operation features a broad range of adjustments. The Synapse allows users the choice of two finger extensionsa hook that wraps the ring finger for a 3-finger configuration as well as a fourth-finger extension. The internal stainless steel components are precision milled for exceptionally crisp operation and flawless cocking of the trigger activation lever. The thumb button is multi-position configurable, with lockable adjustments for trigger travel and trigger tension. The trigger pressure is adjustable from a range of 1.25 to 20 ounces.