17 mm x 40 mm x 12 mm 17 mm x 40 mm x 12 mm NKE 30203 NKE Bearing

NKE Bearing offers 17 mm x 40 mm x 12 mm a UBC Mechanical Electronic Instrument Co., Ltd. 17 mm x 40 mm x 12 mm 17 mm x 40 mm x 12 mm NKE 30203 NKE Bearing selection of Genuine NKE Bearing 6002/c3-koyo SKU: at Wholesale Prices. We are a 17 mm x 40 mm x 12 mm 17 mm x 40 mm x 12 mm NKE 30203 NKE Bearing Certified Parts Retailer

What is 30203 bearing interchange？