Tank "roll"

[Dsix36]

This is how mine works with bungees loped over the tank valves. the top image has the valves down with the clips upward and towards me, this shows how it sits before actually getting in the water.

after getting in the water and the tank rolling it looks like the bottom picture. I lost tanks many times with the clip at 180 degree from the valve, but now I never have one fall out any more.

 

[Dive-aholic]

The only time I have valves pop out of the bungees is when I'm manipulating the bottles to get through a restriction. And even then it doesn't happen most of the time. I've had students come to me with thick bungee and their valves constantly pop out the first dive. We change out the bungee to the thinner stuff I use and the valves stay put the rest of the class.