02 Quickstick oxygen analyzer:

The Nuvair O2 Quickstick is the first diver friendly oxygen analyzer available anywhere! Easy to use...effective...and amazingly affordable! The O2 Quickstick is designed for the nitrox diver who wants the security and convenience of having his own O2 analyzer and does not want to pay a small fortune to own one. Operating the O2 Quickstick is as simple as pointing at the tank valve and "shooting" with only one hand needed! Features magnetic On/Off switch and the replaceable thermally compensated sensor maintains accuracy levels that exceed dive industry standards. 

The unit is totally O-ring sealed for excellent water resistance...and as one of the lowest priced consumer analyzer on the market, you will not be able to resist buying it! The Nuvair O2 Quickstick is powered by a user replaceable 9 volt alkaline battery, has a digital readout LCD screen for measuring O2 content at a glance. No hoses, adapter or cables required. The oxygen analyzer is made from anodized marine grade aluminum and is pocket sized. Unit includes a lanyard and owner's manual.