Also, a couple of things.
One, the AA battery pack fits a little loose in its retaining bracket inside the case of the reader unit. You can hear and feel it sliding back and forth inside of it's captive position - just 1/4" or less - but it bugged me. I put a small piece of stick on foam on either end of the battery pack and it snugged things right up. No more rattle.
Secondly, and this should be obvious to anyone with half a brain (but wasn't to me until Randy pointed out the error of my ways). The sending unit must be in the proper orientation, ie, flat and perpendicular to the measurement source (so that you can read the writing on the side of the sending unit). For instance, the laser will work fine, but the inclinometer will NOT, if it is in this position as shown in one of Bennet's photos:
Again, this should probably be obvious, but I didn't see it explicitly stated in the manual and it got me for sure.
This thing really is cool.