PERFECT SIZEThe 102.125 size is perfectly compatible with the front and rear wheels of most electric scooters. MADE OF HIGH QUALITY RUBBEROur inner tubes are made of thick shock absorbing butyl rubber. These replacement inner tubes are 0.5mm thicker than regular inner tubes, providing higher damping effects. Additionally, these tubes also have chemical resistance, weather resistance, tear resistance, and abrasion resistance. STABLE PERFORMANCEUpgraded thickened rubber tires are highly tear-resistant, scratch-resistant and durable. High quality valves are used to maintain more pressure. Pneumatic tires should avoid piercing sharp objects. INFLATION RECOMMENDATION:Recommended inflation pressure of explosion-proof inner tubes PSI 36 (please note that it is better to inflate according to the recommended inflation pressure of the inner tube, do not inflate according to the pressure indicated on the tire, otherwise it will burst easily).