Featuring a copper metal mixing housing and structure, it ensures long distance sound propagation with enhanced durability against impacts and harsh weather conditions Engineered with erosion resistant ABS components and simplified mounting brackets, this alarm requires minimal maintenance while offering years of dependable service as a critical early warning device Operates flawlessly in corridors, industrial zones, parking lots, and outdoor areas exposed to rain / snow, providing defense against hazards across residential and commercial properties Equipped with a powerful 95dB alarm and rate waterproof design, this 6 inch electric alarm bells delivers penetrating emergencies alerts for both indoor / outdoor use, suitable for 6V 24V or 110V 220V power sources Ideal for school administrators, homeowners, and facility managers seeking stable emergencies notification systems in crowded spaces like classrooms, warehouses, or retail complexes, Manufacturer: Oxxggkao