In my practice set I haven’t this key… when I stop my playing, simply I cover all the holes and the chanter is quiting. When this key functions was implemented? Is it really necessary to break the air flow to stop playing?
Cheers.
Paolo
Your doing the what now???
RORY
the shut off key is really only required when you are tuning drones - the majority of sets don’t have one - don’t worry about it, to stop playing just stop squeezing the bag!
I use a cork in the chanter stock as a shut off key.
Don’t get any simpler than that. Nice to see ya’ Phil. 
The reason you would want a stop key is to free up one of your hands to tune the regs and drones without having to strantgle the neck of the goose or producing noise not conducive to good tuning.
As you do not have regs, you do not need to worry about it.
With the cork I free up two hands so that I don’t pull out a drone accidentally. 
My pipes are being really stubborn just now with this cold snap. I am ready for some more of that global warming. Where did it go??? 
I haven’t been very active (and I am too puny just now to play) due to a bad sick spell and withdrawing from morphine (2 very rough weeks). I had been bedridden for almost two months and I am so sore and weak. 
It ain’t in Florida right now either… do you suppose Castro’s got it? 
Ok, so it has a “real” function!
Cheers 
Here’s a thread about stop valves:
http://chiffboard.mati.ca/viewtopic.php?p=451358&highlight=#451358
and heres one showing different types and how they work
http://chiffboard.mati.ca/viewtopic.php?t=12665
John