-PROFESSIONAL SKATEBOARD BEARINGS. -100%HIGH PURITY SILICON NITRIDE CERAMIC BALLS, GRADE 3. -TITANIUM COATED RACES, BLACK SHINNY EFFECT. -25% FIBERGLASS RE-INFORCED HIGH SPEED NYLON BALL CAGE. -EXTREMELY HARD & FAST, UP TO 120.000 RPM. -SINGLE, NON CONTACT, ...