8 black pieces Pink is a reference for the same product in a different color when actually attached. Whether the circular rubber attaches to the wheels: ⭕❌ ✱ See image Even if the rubber is slightly distorted, it will fit when attached. For black: The grooves may be difficult to see in the photo, but refer to the pink one. Align the direction of the caster cover grooves with the side that pulls the suitcase and attach it. If you attach it incorrectly, the groove direction will not match, and you will have to redo it. Shipped via Yu-Yu Immediate purchase is OK Suitcase caster case Suitcase wheel cover Suitcase tire cover Suitcase Carry case tire cover Carry case wheel cover Caster cover Travel goods Business goods Airplane