The 310-4 is a 3 hour fire-rated, industrial electric strike designed for extreme heavy duty applications. The all stainless steel construction of this devices makes it ideal for high abuse applications that would disable other electric strikes. The 310-4 has a unique 3/4" face plate with an integraded 1/4" base shim that can be removed in the field to accommodate rim exit devices with a 1/2" or 3/4" throw latchbolt.This industrial grade electric strike is used with rim exit devices with up 3/4" pullman style latchbolts used on single door openings or at the top of a surface vertical-rod exit device.