A Ring cheekpiece introduces poll pressure as well creating leverage on the mouthpiece.
The Barrie is a severe bit due to the centre links of the two pieces being offset by 20mm giving it a double nutcracker action, which creates more tongue and bar pressure.
Good for strong older horses.
Disclaimer: Sweet Iron will oxidize when it comes into contact with mositure, this oxidation process encourages salivation which improves acceptance of the bit. This process changes the blue colour of the Bomber bit to a brownish grey. If not used for a while, any build-up may be removed with a scourer and wiped with a damp cloth.