8 piece Ceramic 627 Inline Skate Bearings Kit | 627 Bearing Kit 20x47x14mm | 6204 Both have a 13mm hex

Both have a 13mm hex

5x10x3mm Ceramic Bearing This is a 3mm width bearing

The specifications

then the Team XRAY X4 ball bearings are a great option

It is a great and complete bearing kit

8 piece Ceramic 627 Inline Skate Bearings Kit | 627 Bearing Kit 20x47x14mm | 6204 Both have a 13mm hexNOTE: These bearings are ABEC7 size 627 2RS bearings for 7mm axles NOT 608 bearings for 8mm axles. The inner diameter is 7mm which some skates use please check your particular skates to see if this is what you need. If not, we also sell 608 ceramic skate bearings which are for standard 8mm axles with an inner diameter of 8mm. For skaters looking to upgrade from their Fafnir 37K 8 ball bearings these are the best choice. With our National and World