Just a note... both Dive Rite and Dive Rite Express sell O2 sensors... Dive Rite Express sells a sensor that was originally manufactured by Teledyne but later manufactured by AI. Dive Rite (the factory) has delivered O2ptima units without cells or in a few cases containing cells from Dive Rite Express when we were using Teledyne, again when they were from AI, from Teledyne directly and also from AI.
In all cases, the cells were either a Teledyne R-22 or the AI PSR-11-39-MD,
just re-labled. Now the question becomes the which do you like Teledyne or AI cells... which is pretty much
because it's been discussed endlessly here. Currently Dive Rite Express is shipping the AI sensor. With the FX, Dive Rite started pricing and shipping the unit including three AI cells.