ROLL-RING is a simple yet innovative chain tensioner made from a specially formulated polymer. The unique design is based upon a simple toothed ring that can be fitted to horizontal, vertical or diagonal drives in a matter of seconds, simply by placing it in-between the two strands of chain. When the drive is in use, the ROLL-RING deforms to an elliptical shape, due to compression between the strands and completely absorbs any slack in the system. ROLL-RING performs the job of a tensioner and a damper in one, and is ideally suited to applications where maintenance is difficult or impossible.