We offer electric scooter. Cc-279 material: impact nylon size: 5" tire: 4.00-5, 4.10-5 air or pu foam filled tireassembly: insert hub-38l+key 5mm, 40.2l+5mm key the beautiful cambered surface is able to help drain. light, two pieces locking, a good substitute of alloy or steel wheels, fit to electric scooter air or pu foam filled tire 4.00-5, 4.10-5good impact resistancegood corrosion and chemical resistanceall materials are complied with cpsia, rohs, en71 part iii regulations