4 Ring Barrie Bit Sweet Iron - 135mm (Polo)4 Ring Barrie Bit SWEET IRON 135mm (POLO) Mouthpiece: Barrie style, 2 piece with 20mm offset joints (double nutcracker) Smooth side for a milder effect and increased forgiveness. Sweet Iron will oxidize when it comes into contact with mositure, this oxidation process encourages salivation which improves acceptance of the bit. Cheek Style: 4 ring Dutch gag with A ring leverage for poll pressure. Action: Very strong; ideal for highly forward or heavy