In article ,
Ignoramus14507 wrote:

I am looking at two 6204 bearings at McMaster-Carr. One is a regular
double sealed bearing 5972K45 for $7.72. Another is a "PermaLube"
bearing 2349K423 that costs $15.32. According to McMaster, perma-lube
bearings are permanently lubricated and require no maintenance.

But what about the regular bearing 5972K45? If it is double sealed, it
must also have lubricant inside, already? What is different about these
Perma-Lube bearings?

i

No bearing requires maintenance. And after they are not maintained for a
while, they fail. Lubricated for life means, of course, for the life of
the bearing - when it fails, its life is over. Catch-22.

I'd say the difference is $7.50 in marketing/profit and possibly 10
cents to use better grease. Or more likely $7.599 and .01 cents.

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