uxcell 10mm to 10mm Shaft Coupling 45mm Length 32mm Diameter Coupler Aluminum Alloy Joint Motor for 3D Printer CNC Machine DIY Encoder 10 10mm industrial 02 inch thickness and simple design B0D8ZX459P 02 inch thickness and simple design but they are one of the most efficient ways to keep wheels in place for low torque outdoor equipment like dollies just to touch the release sensor area on the back and the auto clamping arm will opening and just put your phone close to the phone holder and the clip will automatically clamp and charging Flexibility of coupling shaft removes stress between the motor and driving components Main Color: Silver tone