Double .004 latex. Made with medium frame for average-sized palate areas. Creates older, more nasal cow sounds and older bull sounds. Great for high screaming challenge bugles. This call was designed by Rockie Jacobsen. It features a unique lower profile Slotted Chambered Tone Top that is correctly designed to create more nasal cow sounds and higher pitched bull sounds with ease and realism. It sits up in the roof of your mouth with more comfort and quick positioning to obtain all the elk sounds. TST (Tone Slotted Technology) - The Slotted Chambered Tone Top elk diaphragm call is designed to be placed further forward in your mouth behind your upper front teeth; this helps prevent gagging and gives you easier control of the latex. To operate the call, place the Slotted Chambered Tone Top upwards to the roof of your mouth, latex down and open end of the diaphragm towards the front of your mouth.