Universal, Valve Stem & Finger Button Felt. Set of 3 - Various sizes, mostly for low brass, fits many. They are measured here by OD, ID, & thickness. 7/32" ID fits 1/4" valve stems, such as a Conn Sousaphone stem. Contact me if you wish to inquire on larger quantities, or just to verify your model's fit or maybe you need a 4th felt.