Specialized: Tailor-made for MIU COLOR brand pet carrier, this product is exclusively compatible with this brand and not interchangeable with other pet carrier brands Set Composition: Each set includes 1 front wheel (universal wheel) and 1 rear wheel (directional wheel), fulfilling your requirements for partial replacement or repair Purchase Guide: Check your luggage first to identify missing wheel type (front or rear) and quantity. Unsure? We recommend purchasing 2 sets to get a full set of four wheels (2 front + 2 rear), sufficient for a complete replacement One front wheel and one rear wheel