This rough green (also matte or textured) Polycord® equivalent round polyurethane cord has a textured surface that is designed to slip a little. The rough surface has a low coefficient of friction which is useful in accumulation zones, or where jams happen frequently. Use this material in place of standard clear polyurethane when you need the belt to "give" a little, instead of overheating or abrading. Polycord® is a trademark of Habasit AG.