Features: Equipped with a powerful 95dB alarm and rate waterproof design, this 6 inch electric fire alarm bells delivers penetrating emergencies alerts for both indoor/outdoor use, suitable for 6V 24V or 110V 220V power sources. Featuring a copper metal mixing housing and optimized structure, it ensures long distance sound propagation with enhanced durability against impacts and harsh weather conditions. Ideal for school administrators, homeowners, and facility managers seeking stable emergencies notification systems in crowded spaces like classrooms, warehouses, or retail complexes. Operates flawlessly in corridors, industrial zones, parking lots, and outdoor areas exposed to rain/snow, providing defense against fire hazards across residential and commercial properties. Engineered with erosion resistant ABS components and simplified mounting brackets, this safety alarm requires minimal maintenance while offering years of dependable service as a critical early warning device. Specifications: Component : Copper, metal, ABS Size: about 150x150mm/6x6inch Power supply electric : 6V/12V/24V, 110V/220V optional Sound: 95dB Supply electric : multiple for option Package Includes: 1xSecurity Alarm note: 1.Please allow 1-2cm errors due to manual measurement, make sure that you do not mind before you order. 2.Due to the difference between different monitors, the picture may not reflect the actual color of the item.