The local Yammie mechanic says the metal seal is an upgrade and is better than the the original. He claims 5000 miles. My original had 10,000 miles but was caught just in time. Searching around showed me many Yamaha sleds have the exact same bearing here, except the 4 stroke Vipers. Also the new bearing had allen setscrews where the old one was torx. Crappy for an old guy with bad eyes.