Enjoy total control with this harness. You can keep it open, in case you want to use their mouth for various devious things. Or you can plug it up with the hollow tunnel, that extends 1" into the mouth and restricts speech (and keeps jaws apart). The plug is attached to the harness via chain. The harness, itself, features multiple adjustment points for a one-size-fits-all design.
Plug It Up Leather Head Harness with Mouth Gag Specs and Benefits:
Measurements: One size fits all
Material: Leather, plastic, metal
Enjoy having open access to your partner's mouth or keep it plugged up
With the mouth open you can fill it however you wish
With the mouth close you can restrict speed and keep the jaws apart