We use and sell different types of rope. The two basic types are made from braided fibers, one with an inner core, the other without.
The core rope we use for tensioning our drum heads is designed specifically for this purpose. It is made with a braided Nylon outer sheath for high strength, UV resistance, and smooth adjustments. Some of this type of rope has a blended inner core of polyester and Kevlar which prevents most elongation. Options for size, colors, and braid texture are usually available.