The 700 series is a 3 hour fire-rated, industrial grade electric strike designed for extreme heavy duty applications. the all stainless steel construction of this device makes it ideal for high abuse applications. The 712 series is designed to accommodate 1/2" throw latchbolts, and the 712-75 is designed to accommodate 3/4" latchbolts.This commercial grade electric strike is used with cylindrical locks, mortise locks* and mortise exit devices in hollow-metal frame applications when the lockset has a 1/2", 5/8" or 3/4" throw latchbolt.