Myler 3 3/8" Medium Dee with Hooks with Low Medium Wide Ported Barrel Bit MB 33Stainless Steel 3 3 8" Medium Dee with Hooks, MB 33 Low Medium Wide Ported Barrel, Level 3 The MB 33 is the mildest Myler mouthpiece in terms of tongue pressure. The generously wide port allows room for the tongue to pass almost completely under the bit. Because this mouthpiece does not rotate onto the tongue and the port is wide, it applies little to no tongue pressure, working primarily off the lips and bars. The port on this mouthpiece is only 1 "