STI Series - Conventional Fire Alarms Pull Station Covers The STI Series Pull Station Covers help to prevent false fire alarms without restricting legitimate alarms. They consist of a tamper-proof, clear Lexan polycarbonate shield and frame that fits easily over manual pull stations. Some models offer a piercing warning horn when cover is lifted. Fits virtually all pull stations Tested and approved by wide range of fire prevention and testing authorities Guards against physical damage to manual pull station Optional gasket for outdoor use is available Optional battery-powered horn (9-volt alkaline battery included) STI-1200 Pull Station Cover without Horn Mounting: Flush Dimensions Height (in.): 10 Width (in.): 7 Depth (in.): 2.75