These Valve STEM CAPS are part of a replica of a 32 caliber revolver gun cylinder. it is cnc machined from billet aluminum and finished with our superchrome process. it is made for all bikes with a vertical metal valve stem only. it is also a great look on cars and trucks.. A fantastic way to make your wheels stand out! just $39.99 per set of 4. Light weight and safe for all valve stems except bikes with horizontal valve stems.