This
Jointed Rubber Mouth Eggbutt Bit is stationary in the mouth with a mouthpiece that does not rotate around the rings preventing biting of lips. The
Jointed Bit provides motion with rings and mouthpieces. However, The rubber can be destroyed by the horse in certain places, if not used appropriately. This item measures 2.5" rings and comes in the following sizes:
4 1/2'' & 4 3/4'' 15 mm mouth.
5'' & 5 1/2'' 20mm mouth.