Heavy Duty Large Manual Hand Crank Siren 120±2 db with Rail Stand Base

  
Take the product out of the box, turn the handle counterclockwise, and take out the platen and the whole set. Manual Hand Crank Operated Air Raid Siren. By shaking the handle to drive the high-speed operation of the horn, when the slewing wheel rotates, the air from the side of the air generates high-speed high-pressure and the resonance of the window of the fixed wheel simultaneously causes resonance.