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Universal Magnet For Bicycle Bike Cycling Computer Works Speedometer Odometer 100% brand new and high quality Ideal assistant for bicycle training . Make your sports life more free and comfortable. Material:Magnet, Plastic, Metal Size:16mm x 12mm(approx) Color:Black+Silver Quantity: 1 pc Note: No retail package. Please allow 1-3mm error due to manual measurement. pls make sure you do not mind before you bid. Due to the difference between different monitors, the picture may not reflect the actual color of the item. Thank you!