Scooter bearing and Skateboard bearing is normal radial deep groove ball bearing with double-shield or double-sealed. Scooter bearing/Skateboard bearing is standard 608-ZZ / 2RS (8*22*7 mm, ID*OD*W). The precision grade is ABEC-3, ABEC-5, ABEC-7.
Bearing Race: chrome steel SAE 52100 or stainless steel SUS 440C.
Bearing Ball: chrome steel SAE 52100, stainless steel SUS 440C, or ceramic ball Si3N4 / ZrO2.
Bearing Cage: Nylon PA66+30%GF.
Bearing Type: rubber seals or metal shields.
Bearing Lubrication: Kyodo Yoshi, Shell, Mobil.
608ZZ bearings are one of the most widely-used bearing sizes and are used in many scooters, skateboards, roller skates, and inline skates. This is a popular size of bearing used by Razor Scooters USA on their electric and kick scooter lineup.
608 size bearings are also known in the skateboarding world as ABEC-7 bearings.
Note that 2 pcs bearings are required for each scooter wheel, and 16 pcs bearings for each skateboard.