Manual gear owner, turn around to change gear in a hurry.Back on the spot and get stuck. You need one of these boosters to make your driving experience more comfortable.360 degree smooth rotation, refuse to jam.Anti - slip silicone shell, sweat no slip, no odor exposure Special note: this product can only be used under 20km/h as an auxiliary .Make sure the boosters are fixed before driving and don't rely on them too much.Everything is for your safety. Use: 1. Select the appropriate installation position on the steering wheel (generally, it is recommended to install it in the upper corner, of course, depending on personal habits). 2. First, separate the power boosters' buckles and install them in the installation position, then buckle the bottom parts of the power boosters 3. Tighten the two screws with an inner hexagon wrench. 4. Confirm the fixation.Test its stability at a stop 5. If the steering wheel cover is installed on the steering wheel, please remove the u-shaped rubber pad before installing it Auto Spinner Knob Ball Applicable model: most models Colour:Black Material:metal Size:: 63 mm x 22 mm x 50 mm Package Contents: 1x steering wheel booster ball Only the above package content, other products are not included. Note: Light and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.