1. Two types of bearing sizes: ① with an inner diameter of 5-6mm and an outer diameter of 11-13mm, capable of withstanding a peak axial force of 70N and a radial force of 20N, and accepting double row parallel connection; ② with an inner diameter of 8 and an outer diameter of 11-13mm, capable of withstanding a radial force of 20N; 2. The expected annual demand exceeds 200000; 3. Suppliers are required to have supporting experience and IATF16949 certification within the validity period.