Myler Eggbutt Bits. Eggbutt Bits are rounded rings with fixed attachment for the mouthpiece. Available in an assortment of Myler Bit mouthpieces. Function: The Eggbutt uses direct action pressure. When pressure is exerted on the reins the same amount of pressure is exerted on the mouth. The fixed attachment eggbutt has a more direct signal that the rotating loose ring snaffle. The straight side of the the Eggbutt will not pull through mouth and does not pinch. 3 1/2" ring.