Optibelt’s original timing belt engineered and manufactured to exceed expectations. It starts with the fiberglass cords that efficiently transmits more power where you need it.  The cords are counter wound for smooth, non-biased running.  The durable rubber impregnated polyimide fabric increases durability and oil resistance is bonded to the engineered natural & synthetic rubber core.  Fits standard HTD®, RPP®, and MR® pulleys so you get more performance and durability without the need to replace existing pulleys.