BM Quicksilver Replacement Shifter Knob Black Chrome # BM81670 This BM replacement shift knob fits all BM QuickSilver automatic shifters and features a high quality black chrome PVD finish. PVD (Physical Vapor Deposition) Coating used for Durability and Corrosion Resistance. Includes logo top cap and fits shift sticks with 1/2-inch x 20 UNF threads. Features: Replacement Shift Knob for all QuickSilver Shifters Fits 1/2-inch x 20 UNF Threaded Sticks Attractive Black Chrome PVD Finish PVD (Physical Vapor Deposition) Coating used for Durability and Corrosion Resistance Includes Logo Top Cap