Yes. All of Billy's calls have removable mouth pieces so you can change different size holes. He has push in and screw in style. This one is a screw in style.
He makes many different mouth piece materials. Wood, delrin, ivory, buff horn, micarta, corian, etc. He uses delrin as his standard. He says it doesnt swell and affect the sound like bone, ivory or wood. His personal favorite on his caller is micarta.
