Amazon.com: Power Transmission Products For Desktop 3D Printer Special Bearing 608ZZ ABEC-5 8X22X7mm Mute Speed Miniature Ball Bearings ZZ809 for Reprap Prusa i3 Parts 10PCS Ball Bearings ( Size : ABEC 5 ) :
[5-Pack] 608-ZZ ABEC 5 Deep Groove Radial Ball Bearing 0.315 in x 0.866 in x 0.276 in (ID x OD x W) | 8 mm x 22 mm x 7 mm (ID x OD x W) with Double Metal Shield for Skateboard, 3D Printer, Long Board: Amazon.com:
Amazon.com: 608 ZZ Ball Bearings, Skate Bearings Double Shielded Miniature Ball Bearings for Skateboards, Inline Skates, Scooters ABEC 7 Bearing (8mm x 22mm x 7mm) 4PCS : Sports & Outdoors