Hi
I work for Honeywell Aerospace Yeovil in UK, and we are the UK Design Authority for the P and Q type oxygen masks.
The Q is the small facepiece, and the P is the large facepiece, all other features are the same.
What aircraft are you flying with this mask?
If you need other information on UK aircraft oxygen systems please ask.
Paul, can you tell me why the green 'rubber' (or is it silicon) face piece is now made from a different material? I Can't get on with the newer ones and found that on a long sortie (4-5hrs) it was such a relief to remove it. The new 'rubber' has a different feel about it. Probably just as well that I now use a goochie noise-cancelling headset + mic!