Polyurethane is the base material used for these more durable bu****ngs
http://en.wikipedia.org/wiki/Polyurethane
While Energy does make many different polyurethane based bu****ngs on
the market, they are by no means the only manufacture making product.
You can also check with
Check with Prothane for a complete line of bu****ng and the most
complete line of polyurethane motor and transmissions mounts availble
www.prothane.com
and
Daystar for truck bu****ng and shock boots
http://www.daystarweb.com/
