General description Brand new inner tube designed for durability and quality. This product features a straight metal valve stem, specifically a TR13 valve stem style, which fits wheel holes of approximately 1/2 inch. Technical specifications Size: 3.50/4.00-6 Valve Stem Length: about 3.5 cm / 1.38 inch Material: Rubber Color: Black Measurement allowed error: +/- 1-3 cm Compatibility and accessories Compatible with various brands including BMX, Fly, Hi-Bird, JCL, Linhai, Loncin, Sunl, Tank, United Motors, etc. Package includes: 2 x Inner Tube Other information Note: Light shooting and different displays may cause the color of the item to differ slightly from the actual product.