Willie Berg invented Stone lined Mutes in 1935. They are the finest Brass Instrument Mutes available in the World. Sidelined Mutes play perfectly in tune and are easy blowing. For the perfect professional sound all the time, our line of Stone lined Mutes offers many different models to produce outstanding various tonal colors for the Brass player. Included in the many Stone lined Mute features that allow the outstanding colors of sound is the secret formula used to line each and every Stone lined Mute. The growl will give everyone goose pimples, talking into your horn and answering back. Use it together with the Trixie Plunger Mute. Yes, it's the perfect combination. You will wake up the entire music world with a Trixie Rubber Plunger and Pixie All Metal Plunger Mute. Try it!