KATSU Hand Crank Siren, Portable Manual Operated Air Raid Siren Fire Emergency Safety Alarm 110db 990630

• Made of durable aluminium alloy, sturdy and wear resistant
• Hand Held and manual operated Siren
• Sound Rating:110± 2dB(A) @ 1m, Effective range(Diameter): 500m
• The sound depends on the rotation speed of the handle
• Can be used for factories, families, schools, military units, flood control, disaster relief, forest fire fighting munitions, public and industrial occasions

Specifications: Sound Rating:110± 2dB(A) @ 1m Output Frequency:550±20Hz (depend on the speed of the hand) Effective range(Diameter): 500m(in the open environment) Net Weight: 0.6Kg Features: No Power Supply Required. Compact for Portability. Powerful Universally Recognized Sound. Manual Hand Crank Operated Air Raid Siren. Produces a loud adjustable sound of 110 decibels. Made of durable aluminium alloy. Ideal for getting peoples attention, or rooting for your favorite team in sporting events, and many more applications. By manually rotating the handle, the gearbox of the transmission step by step acceleration to achieve the purpose of sound, the sound depends on the rotation speed of the handle.