Mustang Cable Knotted Nylon Rein w/Solid Brass Conway Buckles 3/4 x 7 Round braided nylon rein with four easy grip knots and solid brass conway buckles on each end. Rein features heavy gauge steel wire core inside handle. The steel wire reduces the amount of slack in the rein and helps to aid in lighter hands. There is no stretch or extra slack to get in the way.