While in the pool the other day, my o-ring on my SPG went. Lots of bubbles as I lost tank air until I shut off the valve and ended my time in the pool. Got me thinking that if it had been an actual dive, this would have been an OOA. My question is, other than investing in an AI hose-less computer and transmitter and not have any SPG hose, is there (or could there be) some way for an old style SPG on a hose to be disengaged or shut down during a dive if the o-ring were to go? Just wondering.