Comparison : Item # 6403, 6400 Series Deep Groove Radial Ball Bearings
Item # 6404, 6400 Series Deep Groove Radial Ball Bearings
Item # 6405, 6400 Series Deep Groove Radial Ball Bearings
Item # 6406, 6400 Series Deep Groove Radial Ball Bearings
Item # 6407, 6400 Series Deep Groove Radial Ball Bearings