Product material: 7075T aluminum alloy and copper Loudspeaker DB: 80dB Product size: approximately 6.5 x 4.5 x 1.5cm Compatible vehicles: road bike, mountain bike, folding bike, etc. Handlebar diameter compatibility: 22-31.8mm Product features: compact and lightweight, easy to install, clear sound Specifications: 1. Hidden bell design for a clean look; fits inside the handlebar without interfering with brake or shift operations 2. Copper metal shell provides increased durability and prolonged sound resonance 3. Micro-arc paddle design ensures a smooth, comfortable grip that is easy to operate 4. Waterproof and rust-resistant coating on copper exterior enhances longevity and durability 5. PC base construction is strong and impact-resistant; fits handlebars 22.2-31.8mm in diameter with three included spacers for secure fitment Package Included: 1 x Bicycle Bell Note: 1. Due to variations in monitor displays and lighting conditions, the actual item color may slightly differ from the images shown. 2. Please allow 1-3cm measurement deviation due to manual measurement. (1 inch = 2.54 cm)