STI-1100 Stopper With Horn (9V Battery)This protective cover has been helping to stop false fire alarms around the world for more than 40 years, without restricting legitimate alarms. All models offer excellent protection against physical damage (both accidental and intentional) and several against severe environments both inside and out. It is ideal for schools, colleges, hospitals, nursing homes, stores, hotels and public buildings of almost every kind where there is a threat of false