Reinsman Jr. Cowhorse Smooth Dogbone with Roller is a 3/8" 3-Piece Sweet Iron Snaffle with Copper Roller. 5" Cheeks, 5" Mouth. Extremely good bit if you need help getting your horse's legs underneath him and his hind end down. The three piece mouth contacts the bars at a more severe angle than a two piece, creating contact on new nerves for better control. Copper roller often pacifies a nervous horse and adds slight tongue pressure for better headset.