Here is a link to a replacement guide I have put together.....

5. Small Philips Head Screwdriver: to remove the front/rear cover screws

Differences

Phillips drivers have an intentional angle on the flanks and rounded corners so they will cam out of the slot before a power tool will twist off the screw head. The Pozidriv screws and drivers have straight sided flanks.

The Pozidriv screwdriver and screws are also distinguished, visually, by the second set of cross-like features set 45 degrees from the cross. The manufacturing process for Pozidriv screwdrivers is slightly more complex. The Phillips driver has four simple slots cut out of it, whereas in the case of the Pozidriv, each slot is the result of two machining processes at right angles. The result of this is that the arms of the cross are parallel-sided in the case of Pozidriv, and tapered in the case of Phillips.

Phillips (PH)

Pozidriv (PZ)

So my battery died in my PCV late friday and I didn't want to send it in to SRM for replacement. The cost and downtime is unacceptable so I took it apart and tried to match up the battery. I was able to locate an 80mAh replacement(original is 100) at batteries plus for $8 but it can be ordered on the internet for half that. The replacement takes about 10 seconds with a soldering iron. Simply snip off the old battery and re connect the red lead to the + and black to - the 80 is slightly smaller than the original so a wrap of electrical tape keeps it tight in the case. So far it works perfectly. I imagine the stand by time will be reduced by the slightly smaller battery but not by much.

1st picture is the original SRM battery. 3.6v 100mAh
2nd picture is the inside of the case where the battery goes
3rd picture is the battery cells taken out of the shrink wrap.
4th is the battery replacement found at batteries plus for $8(stock internet photo)