Reverse DIN Valve

[DogDiver]

I saw an interesting item on eBay today. It was a ScubaPro MK 20 with a cylinder valve but it had the female end on the regulator and the male end on the valve. Could someone give me some history on this unique item? Ken

[Genesis]

I believe that's a new EU thing for Nitrox...... and its NOT good....

[hans471]

I had seen these a year or two ago on European equipment. I wouldn't want it here, very UN-standard in the USA.

[TerryK]

I saw one about 10 years ago - I believe at DEMA. I think, as Nitrox was growing in popularity and it was obvious to the gear manufacturers it wasn't going away, the idea of a unique reg-valve connection came up so an air diver wouldn't inadvertently hook up to a nitrox tank. If you're a jaded individual you might say they came up with the idea just to sell more gear:)
Obviously, the idea never took hold - at least in the US.

TKilleen is right. It came out in 1996, but made its first appearance in the 1997 Equipment Selection Guide.

Nitrox was just hitting the recreational diving sector (only four years removed from Skin Diver magazine's "Just say no to nitrox" issue - November 1992), and all the gear manufacturers were in a tizzy. "What happens if someone uses a nitrox regulator on regular compressed air?"

So this was some genius' answer. You bought a dedicated valve for your cylinder, and the matching Mark 20EAN, and there was no way you could accidentally mix it up.

[DogDiver]

Thanks guys, I'm always interested in diving history....funny how Aqualung has reinvented the double hose regulator.... Guess I'll get my Aquamaster out and dust it off.....lol Ken