CURTIS introduces the second version of the polycarbonate transparent mouthpiece. This model features a unique outer corrugation design, which is visually stunning and uniquely tonal. With a cup diameter of 25.8mm, this mouthpiece is our most popular size, and similar sizes include the Greg Black 5G, Schilke 52, and Bach 5G. In addition to reducing lip fatigue, it is also excellent for outdoor events in cold weather.