? quality, reliably tested inner tube. ? High quality butyl rubber: Made of high quality butyl rubber composite material, with good air tightness, heat resistance and durability. Every product is rigorously screened before it is delivered to you ? Excellent shock absorption ability : The heavy, strong, highly durable butyl rubber made from these inner tubes is a perfect shock absorber to reduce vibration and eliminate the shock caused by bumps and rough surfaces on the road or pavement. Heavy Duty butyl rubber for maximum ride comfort - upgrade your ride experience. ? Check the valve position to ensure that the installation direction is correct. ? Tip: Before installing the inner tube, please put the inner tube into the water for inspection, if there are bubbles, it means that it has been damaged, you can contact us. Check the valve position to ensure that the installation direction is correct. Note: The inflatable inner tube should avoid puncture by sharp objects.