Castell – AI-FSAL-1-KFBT/ASSY – Single Key Access Interlock, Bolt Trapped (AI S

The Castell AI-FSAL-1-KFBT/ASSY is a mechanical single-key access interlock (trapped key) designed for safe door access control in industrial guard or safety systems. In the KFBT (Key Free Bolt Trapped) variant, the bolt remains trapped until the correct key is used, preventing opening of the door unless safety conditions are satisfied.