Designed for use with the bottom bolt of a flushbolt set. Spring loaded plunger returns to floor or threshold level anytime flushbolt is retracted, eliminating the need to clean out the bottom strike. May be used with carpet or threshold application by omitting face plate. Packed unassembled with plate, strike, fasteners, and spanner wrench. Barrel is 1"dia. x 2-3/16" deep. Plunger is 3/4" diameter.