Features: Pre-lubricated, smooth and flat bearing surface, compact structure, with strong bearing capacity and dust-proof, long service time. Single-row design, suitable for high-speed, low friction, low-noise and low vibration, improve efficient and steady work. High temperature quenching forging, sturdy and durable in operation, these deep groove ball bearings combine radial and load at high speed. Mainly applicated on wheels for cars, bike, motorcycle, karts, lawn mower, skateboards, roller skate, tractor, trike, trolley etc. Specification: Model: 608ZZ Material: Bearing Steel Color: Silver Tone Seal Type: Double Metal Shield Inner Diameter: 8mm / 0.31" Outer Diameter: 22mm / 0.87" Width: 7mm / 0.28" Static Load Rating: 1.3kN Dynamic Load Rating: 3.3kN Grease Speed: 34000RPM Oil Speed: 40000RPM Package Includes:20 Pcs Deep Groove Ball Bearings