Made of anodized aluminum,with high strength and corrosion-resistant.Not easy to break, more durable. Fits most non threaded shifters manual transmission,such as for BMW,VW,Jeep,Saturn,Fiat and so on. SIZE:Outer thread pitch: M12x1.25;Inner adapter diameter:13mm Fit almost shift knob with 12x1.25 thread pitch,especially suitable for most of shift knob. Note:Please check non threaded shifter diameter before placing order.