Bike Tires Size: 18 X 2.125 inch (ETRTO: 57-355 mm); MAX Inflate to 40 PSI. Bike Tubes: 18”x 1.75"-2.125". Valve Type: 32 mm Schrader Valve. Suitable for old tires with a tire diameter of 18 in and a width of 1.75-2.125 in. High Quality: Our kids bicycle tires are made of high-quality rubber material, which has excellent wear resistance and shock absorption. The tightly raised tread pattern makes the bike tire effectively anti-slip, ensuring the safety of children during riding. So whether your child is riding on trails in the park or on flat pavement, he'll have a smoother and more comfortable ride. Universality: Our bike tires & tubes fit most kids bike. You just need to choose the right size according to the wheel size of your bike, we offer tires in 12.5"x2.125" / 14"x2.125" / 16"x2.125" / 18"x2.125" / 20"x2.125". You can also choose the color your child prefers between black and white. Please Note: The 18 X 2.125 inner tube and tire are delivered folded. We hope you to have a better tire changing experience and get the best performance from your new bicycle tires. We recommend that you unfold them and leave them for 1-2 days before installation. It will help the tire regain its natural shape and make installation easier. Before ordering, please check the dimensions and details of the bike tire carefully. Package Include: 18 X 2.125 in Bike Tires(Black) *2, 18"x 1.75"-2.125 Bike Tubes *2 and Tire Levers *4. The tire levers make make removing and installing tires easier. 2Pack Folding Bike Tires 18 x 2.125 Inch, Replacement Kids Bicycle Tires Puncture-Resistant and Inner Tubes, with 4PCS Tire Levers, Black