Description The hand-operated alarm is a hand-operated sounder that does not require power support. It is called differently due to local differences (manual alarm, manual alarm, manual alarm, portable alarm, no power alarm) . The utility model comprises a handle, a gear speed increasing mechanism, a clutch slider, a fixed wheel, a sound wheel, a sound window cover, a gear box body and a box frame, wherein the handle is connected with a driving shaft of the gear speed increasing mechanism, and the output shaft of the gear speed increasing mechanism passes The pin is connected to the clutch slider, and the clutch slider is frictionally connected with the flange of the impeller. The purpose is to provide power to the alarm by shaking the handle without the need for power support. The size of the sound depends on the hand speed. It is divided into a fixed hand alarm and a portable hand alarm from the style and use. Features: Hand-operated sirens are lightweight, easy to carry, detachable, and sound an alarm when the handle is held. The hand-cranked alarm plays an active role. When the power and traffic are blocked, other mobile alarms cannot enter the alarm area, and the portable and convenient hand-crank alarm becomes a very convenient and practical alarm. Widely used in factories, schools, military units, flood prevention, natural disasters, open-air military camps, air defense, mountain rescue and seaside anti-ship, forest fire prevention, flood control, fire protection, prisons, reservoirs, ships, mines, plains, pastures, gas stations , airports, forest farms, hotels, hotels and other emergency venues. The essential items for emergencies in any place can effectively provide timely warnings and reduce peoples property losses and casualties. The plastic case makes the alarm lighter and more convenient to carry. Specifications: Condition: Brand New Material: ABS Color: Red + Black Package Weight: Approx. 705 g/ 24.9 oz Size: Approx. 18.6 x 18.6 x 17.0 cm / 7.3 x 7.3 x 6.7 in Output frequency: 55020 Sound level: 1102 (Class A) at a radius of 1 meter Package List: 1 * Handheld Alarm 1 * Storage Bag