I believe I purchased this about 30 years ago. I kept it in storage without using it. I replaced the battery, and the stopwatch function works, but since I haven't attached it to a bicycle, I don't know if the speedometer works. The LCD screen has some slight browning due to aging. Please understand that this is an old item. [High-Precision Cycle Meter] The SANDEN ML-31 is a high-precision cycle meter for measuring accurate speed and distance. It's perfect for understanding your performance while cycling. [Easy-to-Use Design] It has a compact red design with high visibility and is easy to operate. You can use it intuitively with button operations. [Multi-Function] It displays information such as speed, distance, and time, and firmly supports your cycling records. - Brand: SANDEN - Model: ML-31 - Color: Red - Accessories: With cable - Functions: Cycle meter Thank you for viewing.