Size:Outer diameter 6.8mm, total length 18mm, internal thread 5V2 The regular checking of tyre pressure is an absolute must. It will increase tyre life span, lower fuel consumption and increase driving safety. This extension valve cap is screwed on instead of the original valve cap and doesn't need to be removed to check air pressure or to add air. Gauging and inflating happen directly through the valve cap. It is very easy to check tyre pressure without losing your valve caps and effectively prevent gradual loss of air so as to help to save real money. It is really a pretty extension adapter that can guarantee your safety from many aspects. 1. Chrome plated brass surface made it durable and water repellent. Increase life span of original tyre valve screw. No pressure loss even when the valve core is damaged or dirty. Easy to check tyre pressure without the chance to lose your valve caps. Easy to install - simply screw onto current tire stem, no additional dust cap required. Package Included: 4 x Valve Cap Stem Extensions Note: 1. Please allow 1-3mm error due to manual measurement. Thanks for your understanding. 2. Monitors are not calibrated same, item color displayed in photos may be showing slightly different from the real object. Please take the real one as standard. 3. Please check as much as possible to make sure the item is the one that you needProducts from Chunchuan's store