The Buzz Extension Resistance Piece helps to hone the part of everyone's playing that is basically the most important of all, buzzing of the lips. The "BERP" attaches to the leadpipe, and the mouthpiece is placed into it. Then as you play, the air is expelled out the sides of the BERP, not into the leadpipe. This allows you to train the embouchure to the desired pitch. Made in the USA.