Single Horse Driving Lines 5/8 Inch Wide Dark Brown Beta, 20 Feet Long. The lines have buckle ends with double stitching. Reins are made from beta or biothane. Beta is a synthetic leather. It has the look and feel of leather, but is stronger and easier to care for. All you need to do is wipe it down with a little soap and water. You can also submerse it in bucket of water or spray it off with a hose. Great for show or general driving.