10-Pack Sealed Bearings 5x10x4 Miniature VGroove Bearing it uses a set screw

it uses a set screw locking style to grip the shaft

635-Z Deep groove ball bearings single row Radial Bearing 5 mm ID x 19 mm OD x 6 mm Wide

FHFD205-16G Flange Light Duty 2 Bolt Unit Ball Bearings

UCF-211 FYH Bearing

10-Pack 606ZZ Miniature Shielded Bearings

10-Pack Sealed Bearings 5x10x4 Miniature VGroove Bearing it uses a set screwBall Bearings 5x10x4 Sealed Lot of 10 Bearings 10 Sealed Ball Bearings, this is a popular size that could be used in many RC wheel and motor applications that uses this size 5mm x 10mm x 4mm. Bearings are can rotate up to 60,000 rpm, each bearing has 2 Seals to protect the bearing from dust or any possible contamination, additionally, these bearings come pre lubricated with grease for smooth operation, Bearings are packed 10 bearings in one plastic