Professional's Choice 7 Shank Collection dog bone Bit has quite a bit of weight behind the mouth piece to allow quick release from riders hands. This is a great bit out of an O-ring or D-ring. With a shank of 7 and mouth 5 1/8`  the dogbone encourages more flex and bend than a traditional two-piece snaffle.
This dog bone has a roller and is a great soothing tool for an anxious horse.

7 Shank Collection

The Dog Bone

5 1/8`