on\off systems for screw in N2 tanks

[PowerFedMag]

what is a cheap way to be able to turn my screw in 68ci N2duck tank on and off, while still using my KAPP cradle?

I am currently using an ACI rear remote screw in knob, which is somewhat unreliable, because the knob can unscrew it self on my knee sometimes, or screw itself in so far that it cuts off air.

[Russ]

A cheap way? Quality doesn't come cheap. Both KAPP and CP make a real nice on/off (about 30 clams). I have a CP lightning drop with a CP on/off on my Spyder, nice stuff, and works great. They're made both with and without the armageddon-type dovetail. You'd need one without it.

[PowerFedMag]

ok

I did a wee bit o research.
My KAPP Cradle is called the KAPP Pro-Series to be exact (in the 88pball catalog, fits raptor!).
I went to KAPP.com and I am not sure if their on\off system would work.
It says it fits the DZII and stuff, but I don't kno...I'm just tired...

[PowerFedMag]

so

does anyone kno what on\off system I CAN use on the pro series KAPP cradle I gotz?