SG9 Bearings from Rollerblade, the world leader in inline skate technology, combine a high level of precision, expert engineering and quality of materials to deliver an amazingly fast, long lasting skate bearing. They are protected with a proprietary mix of silicon and grease to keep the parts rolling smooth while preventing road grit from getting in. These inline skate bearing will make old skates roll like new ones and are ideal for a speed increase or simple replacement of older worn out bearings. The higher the number at the end of the bearing indicates a higher level of precision, tolerance and speed. Includes 16 bearings.