This belt is of recent manufacture. These belts are made using state-of-the-art vulcanization chemistry, forming highly cross-linked polymetric structures which ensure long-term elastic stability.

Prior to installation of your new belt, the belt path should be cleaned.  Suggest you use common household rubbing alcohol (isopropyl) or a similar solution to clean the old, (often invisible) belt residue from the surfaces of the entire belt path, so it doesn't contaminate the new belt.