Kevlar is just a word to these manufacturers -at least some.One would think kevlar would be the longest lasting.
How many years do belts typically last?
Aramid is another.
The quality and even correct size and cut angles on sides etc varies a lot by brands.
The longevity also varies greatly.
-- A 5/8 x 102 Kevlar belt is not the same as every other 5/8 x 102 Kevlar belt.