When we talk about ceramic bearing, we are typically talking about a couple of types, there is the Zirconium dioxide commonly referred to as ZrO2 (it's formula). The ZrO2 is typically the bearing that is a full ceramic bearing all white balls and races.
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Skateboard wheels mostly use 10mm spacers, (a few longboard skateboard wheels take the smaller 8mm). Quad Roller Inline Skate wheels use 8mmspacers. Set of 8 - Quad Roller & Inline Skates. Set of 4 - Skateboard.
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Hardness: HR 82a. Fit all quad skates.
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Bauer XLP Quad Roller Skates with Air Waves wheels: A great value skate with urethane wheels, perfect for indoor and outdoor use. The Air Waves Wheels are fitted as standard with Abec 7 bearings. We fit ABEC 7 speed bearings.
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Hardness: HR 82a. Fit all quad skates.
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PREMIUM HYBRID 608 RS CERAMIC BEARINGS ROLLER SKATE 8x22x7. Then there is the Silicon nitride referred to as Si3N4 (it's formula). In essence the higher the number the smoother the bearing allowing for better speed and longer free roll.
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Name：Silicon Nitride Ceramic Bearings with Cage Material：Silicon Nitride（Si3N4） Inner Diameter: 3mm-50mm Tolerance: ±0,0002 mm High Temperature: 1200℃ Number of rolls: Single row Standard part: Yes
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These wheels are used for the modification of outdoor sports enthusiasts' roller skates or the maintenance and replacement of accessories.SpecificationColor: PurpleMaterial: PUHardness: 82ASize: 32 x 58mm / 1.26 x 2.28 inch(H*OD)Packing List: 4 x Skate Wheels, 4 x 608RS BearingsAdvantage1. Made of polyurethane, outdoor wheels have the characteristics of non-slip, good compression resistance, and shock absorption, making sliding more comfortable. They has good wear resistance and a long service life.2. The wheel has a wide contact surface with the ground and has a strong ability to pass obstacles. Skate accessories can smoothly pass through various roads, such as gravel roads, brick roads, and speed bumps.3. Roller skate tool has a good rebound, making it faster and more stable in grip.
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