The Gates Century Series Stretch Fit Belts, with self tensioning technology, is engineered for exact fit and optimal performance on stretch fit drive systems. The patented highly engineered EPDM belt ribs are resistant to oil leaks, wear and pilling. New TwistLock technology provides the strength and flexibility of advanced polyamide tensile cord, and the specially formulated adhesive gum locks onto the belt cord allowing it to elongate and stretch but never fail