Twisted combination rope has the best of both polypropylene and polyester ropes. The polyester jacket creates a stronger layer than an all polypropylene rope; the polypropylene core makes the rope lightweight yet strong and water-resistant, so its good dielelectric properties will keep it from conducting an electric current if it touches a live wire. it's also extremely resistant to mold, mildew, rotting, petroleum products, marine organisms, and most alkalis and acids and retains its strength even when wet. The twisted construction makes it easy to splice so it's ideal for a wide variety of uses, including safety rope, dock line rope, lock line rope, guy rope and electric utility rope.