Usage Tips:Description:Material: SiliconeSize:8.5*3.6*3.2cm/3.3*1.4*1.2"Color:blackFeatures:1. Product is lightweight. Does not affect the appearance of the bike and increase the burden of riding.2.Adaptation: Bairton; Garmin; Magene3.Installation steps: Install on the non-drive side, and press the flat side of the pedal to the inner crank, Wrap the belt around the crank and tighten it to hook the pedal sensor4.Bicycle cadence sensor silicone protective cover, durable silicone material, can be extended twice, effectively prevent sand.NOTE1. As we all know ,the different computers display colors differently,the color of the actual item may vary slightly from the following images.2. If you feel difficult to choose the size ,you can feel free to contact mewe will give you some suggestion,but it is for you reference only.3.We could accept Mixed items,Colors And Sizes Order. The more quantities, the more Package include: 1 pcs* Cadence sensor cover