Usage Tips:1. This Bicycle Valve is Made of Brass and Closely Matched With Rubber O-Ring, Which Can Effectively Prevent Leakage. The Valve Cover Can Prevent it From Being Corroded By Muddy Water. 2.[PRODUCT DESIGN], Portable, Easy to Install, Presta to Schrader Adapter, Just Loosen The Tip of Presta Valve, and Then Screw on The Valve Adapter, Which Can Help you Improve Efficiency and Inflate your Bicycle at any Time. 3.[EXTENSIVE USE]These Valve Stem Adapters are Suitable for Bicycles, Road Bikes, Folding Bikes and Most Mountain Bikes. They are Very Easy to Inflate. Enjoy your Bike Trip With our Accessories. 4. [YOU WILL GET]6PCS From Presta to Schvadr Valve Adapters, 12PCS Presta Valve Covers, Which Will Greatly Meet your Demand. 5.[MULTI-PURPOSE ADAPTER]The Bicycle Valve Can Be Converted Form Presta to Schwader, Which Can Be Used to Inflate Tires With Various Standard Pumps or air Compressors. Product description I wish all the bicycle lovers over the world can enjoy the happiness ,I am deeply honored. Colour:Gold and Black Material:metal and plastic Size:outer diameter 9.9mm, length about 12.7mm Package Contents: 6 x Presta to Schrader valve adapters 12 x plastic Presta valve cover Only the above package content, other products are not included. Note: Light and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is 1-3cm. Note: Due to the light and screen setting difference, the item's color may be slightly different from the pictures. Please allow slight dimension difference due to different manual measurement.