The MICROAXS MX-45F-24V fire-rated Grade 1 strike is specially designed with a durable, stainless steel die cast body. It is engineered with corrosion resistant components with fewer moving parts for maximum life. The standard unit includes monitoring outputs, field-selectable voltage, and field-adjustable operation (fail-secure or failsafe.) Designed for use with cylindrical and mortise locksets with 9/16" - 3/4" throw latch bolts.