Rubber Master 6" Tire Inner Tube with TR13 Rubber Valve Stem Implement Cart Wheelbarrow fits 4.00-6, 4.00x6 Designed for Wheel Barrow and garden equipment Fits Sizes: 4.00-6 Tube has Standard TR13 valve stem: Straight rubber valve, the most common stem style, measuring approx. 1.38" long and used in the standard size wheel hole of approx. 1/2"