Because it's handmade, each shift knob has a unique character, including the wood grain and shape. It can be installed on both manual and automatic transmission vehicles! Note: It cannot be installed on automatic transmission vehicles with a shift knob that has a lock button. To ensure it can be installed on any vehicle, we offer a free service to drill holes to match your bolt size. Please provide the bolt dimensions for accurate installation. Material: Japanese Zelkova Length: 19.0cm, Diameter: 2.8cm Shape: Octagonal