Pony bottle valve, Pro vs DIN?

[elan]

I suppose that "pro" means DIN-232 bar and "DIN" means DIN-300 bar.
I think it is a very bad idea to mount a DIN-300 bar valve on a tank not rated for 300 bar. It is dangerous, there ia a serious risk that the tank is over-filled!
The valves are different exactly for avoiding this risk.
Depending on where you live, installing a 300-bar valve on a tank not rated for such a pressure could even be a crime!
Finally also consider that a DIN-232 bars valve can also be used with a yoke reg (or can be filled with a compressor equipped with yoke connectors). So it is much more versatile...

Its legal to have the valves that are deep (300 bar ) on any tank here. In NA the service pressure of a valve is dictated by the burst disk. We do not even have 300bar tanks here. And its common to have shallow (200 bar) valves on 232 bar tanks (called HP here)

 

[jborg]

A 232 bar tank with a 300 bar valve would have people running for the hills, here. It's certainly against regulations.

As @happydiver is obliquely hinting at, it is indeed not possible to hook up a 300 bar fill whip to a 232 bar valve. That's the main point of having the two different valves. (I've actually been looking for an adapter to allow fitting a 300 bar fill whip to a 232 bar valve for ... reasons, but they're hard to find, for the obvious reasons.)

Having a 300 bar valve in the US seems utterly pointless.