Excellent volume. More compact size. That's what "The Threat" Bugle tube is all about. Rockie has done it again by creating the V.E.T.T. (Volume Enhanced Tone Technology) system that creates true, easy to obtain elk sounds. The V.E.T.T. contains a spring, tuned to the right dimensions, inside the special made mouth piece adapter. The spring helps create more volume, stabilize higher notes, raspier low growls and easier octave changes with less air pressure. The spring allows for the right amount of vibration to enhance the tone quality and volume when operating the call. "The Threat" comes fully assembled and ready to challenge the biggest bulls! The grunt tube's overall length is 18 inches making it easier to pack. With it's 1 inch mouth opening and tapered lip adapter there is more comfort and control of all your bull elk sounds. The vibration dampener (Tube Tamer) is on the inside of the tube on the large end. This helps enrich the deep sounds for chuckling and helps eliminate any plastic vibration. No more "tuby" sounds. The Threat will help get more elk to respond as it has already done for many elk hunters in the field tests. Get the volume and tone of a large tube, in a more compact size!