These designs tend to be smaller as they do not need the air bottle.
He slipped off his air bottle and Dillon reached for it.
He attached the regulator to the valve of an air bottle.
Let it stand that, in addition to seasickness, my air bottles were playing out.
The Brigantes had brought quite a mound of air bottles for themselves.
I'd let him hold the last air bottle while I took a leak.
Then they swung the spare air bottles over their shoulders, and passed out through the lock.
But I took a compressed air bottle in the lock with me.
It didn't have air bottles and I had to live on the air inside while he got three shots.
Then we will risk going to the surface, clearing the hold, and filling our compressed air bottles.