<p>Important note：</p> <p>Before changing the tube,please check whether have some stones or sharp things that may broke the tube that stay in your tire   ,if have pls clean it.</p> <p>When changing your bicycle inner tube ALWAYS be sure to add just a little air to the tube before installing. This gives it form so it doesn't get twisted or bunch up which may cause a pinch flat. Once the new tube is installed and BEFORE fully inflating only add a few PSI to further form the tube. Inspect for an even bead of the tire to the rim on both sides.CONTINUED.....Then, inflate to approximately half the desired PSI and re-inspect the tire bead to the rim again. If even beading all the way around AND on both sides then inflate to the recommended air pressure. This procedure is important because if the bead doesn't hook properly on the rim then as the inner tube is inflated it can sneak out between the tire and rim and go BOOM!</p> <p>Specification :</p> <p> </p> <p>Labeled Size: 16 x 1.75/2.125 Valve Type:32mm Schrader Valve</p> <p> </p> <p>Tube Compound: Butyl </p> <p> </p> <p>What is in the box :</p> <p> </p> <p>2 pack 16 inch bike tubes and 2 Tire Levers</p> <p> </p> <p>SATISFACTION GUARANTEED: If for some reason, you are not 100% satisfied with your purchase, you can return it for a full refund!</p>