Check the listing for details. Reinsman Dogbone Roller Snaffle D-Ring Bit. Condition: New. Listed at 88.28 USD. Reinsman Dogbone Roller Snaffle D Ring Bit Designed to apply pressure to lips on the opposite side of the face to help horse turn. Mouthpiece breaks over the bars at a different angle to contact new nerves and add some tongue pressure for better control. The copper roller and sweet iron bars add that sweet & sour taste for better moisture and will act as a pacifier for many horses that like to chew on the bit. The copper roller and sweet iron bars work together to cause the horse to salivate which keeps the horse's mouth soft and responsive. Sweet Iron is intended to rust and it actually has a sweet taste to it as the rusting occurs. This causes salivation in order to increase suppleness and lubrication.3" Dee. 5" Mouth. 7/16" 3-Piece with copper roller.