1This bearing wheel is special design to fit for DJI RoboMaster S1. 2Made of quality material, which is durable, wear-resistant and has good performance. 3The rubber wheel with good friction and shock absorption 4It has excellent cross-country capability and can reduce the hard friction of the hub 5With high standard, low rolling factor and aluminum alloy shaft 6Can be used as a replacement parts to improve your RC robot performance. Simple and easy to install Condition: 100% Brand New Item Type: RC Accessory Wheel Material: Rubber Shaft Material: Aluminum Bearings Material: Stainless Steel Gasket Material: Nylon Color: Black Diameter: Approx. 1.55cm / 0.6in Length: Approx. 3.5cm / 1.4in Weight: Approx. 132g / 4.7oz Fitment: Fit for DJI RoboMaster S1 12 x Wheels13 x Shaft26 x Bearings28 x Gasket