Bought these to replace dried out bearings in my stove's exhaust blower. New blower sells for about $140, 2 of these, $10.50. The stove does run much more quietly, however, the blower does still have some mechanical noise. These blowers were definitely not intended to be serviced, but rather replaced. Getting them apart after years of heat cycling and such is quite a chore.
I'm not sure how long these bearings will last (heat). I may have bought the wrong bearings for the application.
Time will tell.
Service and product were excellent from Boca!