Features: This mechanical stopwatch delivers accurate timing with its robust mechanical design, eliminating battery drain issues in cold environments for long term durability. Featuring metal casing for rustproof and break resistance and simple button controls for easy start stop operate, it ensures long term use in demanding settings. Ideal for students, teachers, coaches, and users who require mechanical timing tools for educational and professional activities. Perfectly suited for physics experiments, sports training, lab research, and outdoor event where precisely timing is essential. This educational stopwatch mechanical timer is versatile timing tool for diverse needs. Specifications: Component: Metal Color: Silver Size: Approx. 8.5x10cm/3.35x3.94in Weight: Approx. 100g Package Includes: 1Piece Mechanical Stopwatch note: 1.Please allow 0-1cm error due to manual measurement. Be sure you donot mind before bid. 2.Due to difference between different monitors, the picture may not reflect the actual color