For sale is a gently used Palm O2 pocket O2 analyzer. Sensor is about 6 months old and has about 4-5 uses, entire unit is a few years old and has probably 40-50 tests total. I use it primarily to teach Nitrox class, however I would like to move to a Helium analyzer since I am teaching Trimix more and more. $200 and I will ship and insure to the lower 48. Paypal only please.