For high profile rims. An advantage of this extension is the application between the valve body and valve itself. Protruding from the rim is the valve, not the extension. Ease of inflation, adjustment of tire pressure or deflation. Extensions are equipped with a seal, self-deflation is not possible. Aluminum valve extension in sizes 20, 28 and 40 and 60mm, superlight, for deep dish rims. All of our valve extensions could be stacked to achieve the optimum length.