Observe: For those who enter key word "6303RMX" into eBay or Amazon, you will note The supply of o.e.m size bearings - 10X42X13. "6303RMX" is stamped to the OEM idler #2 bearings. I've strong doubts about these getting high-quality bearings, including the Koyo bearings labeled as becoming built in Japan due to the fact this bearing isn't at present