Lockable gags

There are form memory materials, that switch between different geometries.  The switch is triggered by light, electricity or even magnetism:

Form memory polymere

I wonder if it's possible  to use something small to insert the mouth that changes it's form to fill the space behind the teeth when switched.

Not a solution aeady at Wal-Mart. But maybe a kinky chemist  is reading this  😉

As mentioned before, gags with a single strap (even if it is lockable) can easily be removed, especially with hands free.
The only secure option that is not a hood would probably be a lockable head harness or a "standard" head harness that you can fit some small padlocks on (e.g pulling them trough the same spot as the closing pin of the buckle and going through the next hole of the strap, next to the closing pin)
There are different harnesses and gags out there...
example 1
example 2
example 3
...
since i own a model of the last one metioned i can only say the harness can easily be locked by just putting padlocks through the next free eyelet in the locking belt that goes through each buckle, tighten the chin strap and the overhead strap and you can't get the gag out even if you have your hands free (unless you use brute force
 in an effort to ruin the whole piece ofc - even that would be difficult)
that said - if you have your hands free then the use of this inflatble butterfly-gag doesn't make sense at all because you can just open the valve to deflate it 😋

How about a lockable female head mask that has a built in gag?
A wig could hide all the locks and laces.

I have this one with a lockable collar:
   

the mouth-piece is quite effective, but still comfortable

   

I don't know if this was posted before, But this gag may work as Lockable.
Can't remember where I got this Picture.

I don't know if this was posted before, But this gag may work as Lockable.
Can't remember where I got this Picture.

Looks like the work of Gag Snob (Click link) at DeviantArt 

MJ

I had a thought about this a few days ago when I came across a tongue suction sleep apnea mouthpiece.

Basically you squeeze the end of the mouthpiece and insert the tongue into it, then release the end of it with your fingers and it draws the tongue in further.
Sure it’s not lockable but I don’t know if it’s removable without hands.

I had a thought about this a few days ago when I came across a tongue suction sleep apnea mouthpiece.

Basically you squeeze the end of the mouthpiece and insert the tongue into it, then release the end of it with your fingers and it draws the tongue in further.
Sure it’s not lockable but I don’t know if it’s removable without hands.

I have a latex mask with an integrated mouthpiece which is similar. There is some suction when I push the tongue in that holds it in place, but it's easy to release the suction by rolling the tongue.
Also, after a while, the suction becomes uncomfortable and it feels like the tip of the tongue gets numb.
Besides that, the mouthpiece is quite comfortable and effective to muffle noise.

Where did you find it?
eBay?

[Like Ra]

There are links to similar gags and hoods in the eBay and Ali threads.