Timney Triggers AR Calvin Elite Trigger, 1.5lb Pull Weight, Adjustable Shoe, Red Finish 660CE Timney set the standard for aftermarket trigger upgrades for the AR/M4 rifle. This trigger features Ultra-reliable 5-pound hammer spring coupled with a crisp and zero creep 1.5-pound pull weight. Trigger shoes are adjustable for length of pull" cast and height for the ultimate in custom comfort and positive contact.