I bought my checkmate from Wings and Wheels www.wingsandwheels.com
It matches readings on medical units in my testing.

I used it to calibrate my O2 system, which I had never used before. Nelson
A4 + Oxymizer "mustache"

Found the flowrate that kept me above 90% at 14-15 000 was just as marked on
the flowmeter! It was reassuring that it was working as it should. Was at
Moriarty, hooping for 17,999 but never got there. Once I was sure the system
worked, I only "spot checked" from time to time.

Saturation would vary with system performance and state of health. Usually I
fly at altitudes lower than the ground is at Moriarty! I am a few days short
of 67 and I used to smoke many years ago. I intend to spot-check when at
oxygen altitudes from time to time. I would recommend the same to anyone
else unless thay are 19 and never smoked.

--
Hartley Falbaum


"KP" wrote in message
oups.com...
Hi All
Would like to buy a blood oxygen saturation monitor! Which is the best
one and where on the internet to but it? Or is this one more gadget to
do without.

Ken (KP)