American Shifter company's adapter kits allow you to install your shift knob with ease. You can simply insert the correct adapter and screw onto your shift lever. It comes in 2 kits as standard or metric. It includes one 16 millimeter x 1.5 to 1/2 13 adapter, one 16 millimeter x 1.5 to 1/2 20 adapter, one 16 millimeter x 1.5 to 1/4 25 adapter, one 16 millimeter x 1.5 to 3/8 16 adapter, one 16 millimeter x 1.5 to 3/8 24 adapter, one 16 millimeter x 1.5 to 5/16 18 adapter, one 16 millimeter x 1.5 to 5/16 24 adapter and one 16 millimeter x 1.5 to 7/16 14 adapter.