The Big Ring Gag is stronger than the usual Loose Ring and Eggbutt as the ropes going through the rings create leverage which will exert more pressure through the mouthpiece whilst at the same time introducing more poll pressure.
The Elliptical is a 45 mm lozenge, it is stronger than the Control Plate due to it having a smaller surface area. Consequently, a horse using his tongue as a means of pushing against the bit and therefore taking control, will draw back and tuck his chin in, coming back to a better point of control.
The Petros mouthpieces rotate preventing the horse taking hold of the bit. Often good for a horse that leans or tries to take hold of the bit.
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.