The Tone Selector - Simply dial the bull sounds desired; small, medium, or large with true back pressure; Expandable outside tube - Overall length of tube when expanded is 23" and collapses to 17", allows for better compaction and ease when carrying; The Tube Tamer produces better sound quality, and coupled with the Conqueror external mouthpiece even novice callers can use this tube. Remove the Conqueror mouthpiece for diaphragm use