I've had a few requests to knock up another batch of these from distressed fish owners who want to blow air from their scuba cylinders into their fish tanks. They're definitely not for use with neat O2 or anything like that, despite what you may see or hear elsewhere. Oh no.
So if you're interested please drop me a PM. £49 delivered.
Every order gets a free oro-nasal bag mask which is just a coincidence, nothing else.