Eggbutt from Bombers.

The eggbutt prevents the horse from being pinched in the lips or corners of the mouth by the bit rings and provides a more stable feel against the horse. The eggbutt keeps the bit steady in the horse's mouth.
The Snaffle Cable has a curved mouthpiece and reduces the nutcracker effect, with the added benefit that the cable's spring action decreases and distributes pressure in the horse's mouth. By removing the center links, an additional pressure point is eliminated, making it gentler than a regular double-jointed bit.