14" [2 pack] THICKER THAN STANDARD INNER TUBE (Heavy Duty 3.5mm Thickness): Designed in San Diego, CA - We have upgraded our inner tubes from production, making them 3.5x THICKER than the originals. Instead of average 0.8 or 1.2mm, we offer 3.5mm thickness! This has proven to extend the lifecycle of your wheels 5x longer - A no brainer. We invite you to compare our products with any other so you can feel the upgraded quality in your own hands. COMPATIBLE WITH BEST BICYCLE BRANDS: Our inner tubes are universal for any tire that has an outer diameter of 14 inches and a tire width of 1.75 to 2.25 inches. Includes 2 tire levers: Tire levers are essential tools for removing and installing bicycle tires and inner tubes. Our tire levers are made from durable plastic and feature a comfortable grip, making them easy to use CHOOSE PEACE OF MIND: We understand families have a lot to take care of and time should not be spent constantly changing tires. For this reason, we have made our inner tubes to last longer. Be aware that it will feel harder when changing the tire because its Extra 3.5x Thickness Material - This is meant to be and know that we work so you never have to replace a tire again! - Have Any Problem? Please Contact Us Anytime. Thickness 3.50mm Butyl Rubber Walls, Heavy Duty inner tubes with valve stems for kids bikes. These inner tubes are butyl rubber, which is more durable, thicker, and more shock-resistant than regular rubber, and provides a longer service life. These inner tubes are made from high quality butyl rubber, which is safe and non-toxic. The valve stem is made of premium steel and aluminum, which is durable, not easy to break or deform, and has a long service life. These bicycle inner tubes are suitable for Royalbaby, Huffy Kid & Joystar kids' bikes. These inner tubes are easy to install and remove. Please use tire levers to make your work easier and safer. These inner tubes are perfect for replacing damaged or flat inner tubes on your kids' bikes, and provide a safe and enjoyable riding experience for your children.