This clutch lock is UL Listed for Fire Rated Frames and Doors. Clutch design resists vandalism and is very durable. Lock is Grade 1 and can be ordered in a variety of styles, finishes and key configurations. Available in Best IC prep and large profile Schlage IC. All of our cylindrical locks have our patented solenoid that is dual voltage and field changeable from EU (Fail Secure) to EL (Fail Safe) without hand tools.