The SD-558A Bicycle Speedometer we are offering here is just the thing you want. It features high quality material and easy operation even for green hand. It is not only convenient but also practical and easy for install. The power saving mode and sleeping mode with auto start function are very considering and environment friendly. You can have the average speed， maximum speed， relative speed， riding time and total riding distance all at the same time. With it， you can check data freely and change your exercising plan immediately as you wish. Believe us， you should not miss it!                                    Features            Large LCD screen design allows conveniently useSimple and humanized operation interface The liquid crystal display functionSuitable for all kinds of bicycles and front forkDetachable fixed seat， can be quickly removed while parkingLarge buttons for your convenienceGood waterproof function can make it through even for the rainy days                                                            Specifications             Color     Black !#!amp!*! Silver    <br> Total Trip Time     0:00:00~99:59:59    <br> Riding All Time     0:00:00~9999HR    <br> Odometer Range     0.00~9999km(m)    <br> Temperature Range     -20℃~70℃/-4℉~158℉    <br> Backlight Working Time     PM: 17:00~ AM : 08:00    <br> Auto on/off     Support    <br> Power Support     1 x 1.5V/AG13    <br> TemperatureExceeds Operating Limits     0℃~55℃    <br> Speed Accurate     ±0.1km(m/n)    <br> Dimensions     3.54 x 0.59 x 1.77" / 9 x 1.5 x 4.5cm (LxWxH)    <br> Weight     5.46 oz / 155 g      <br>                                                             Package Includes            1 x Bicycle Computer<br>1 x Magnet<br>1 x Sensor<br>1 x Tie<br>1 xSponge Sticker<br>1 x Mount<br>1 x Fixed Mount<br>2 x Screws<br>1 x Manual<br>