The gag bit is designed to give more control over a horse who becomes string in certain situations. It is commonly used by polo players. The gag has special cheekpieces made from either rolled leather or rope that run through the slots at the top and bottom of the bit rings. This bit is designed for use with two pairs of reins one attaching directly to the bit rings and the other to the ring at the end of the runner. Bit and runners are also available separately.