A little late in my reply, but if you gotta give me a -1 for giving you a twist for not reading the directions, (as Craig pointed out it is written on the paper tab).
, well...lighten up man. Your question was stupid because you did not read the instructions.
There is humor intended, but a word of warning as well.
You admit that you are new to this, and there is a whole lot more to producing clean air that dropping in cartridges and hoping for the best, even air tests are essentially worthless as they give you a moment in time, which may or may not be the same the next time you start the compressor.
I have electronic moisture meters as well as CO meters, (Thanks Peter) and I hand pack. I still weigh my A.C. at filter change (Before and after) to be sure it is not getting overloaded. A multitude of other precautions are taken on a daily basis this serious business and if you do not pay attention and choose not to read instructions (At the very least, I would suggest you do much more and really learn about this stuff) somebody could get hurt or killed.
What did Mike at L.F. say..some shocking number of dive shops coming back with high moisture content in their air, I forget the figure.
Despite what the books that come with the compressor say, this is not plug and play.