Recommend alignment protractor


Hi,
Can anybody recommend an alignment protractor. I bought a geodisc, but now that I have it in hand, I think I may want something a little more precise. I'm using it on an Immedia rpm-1 table and arm (unipivot).
jj2468
A quick caution in re: the ttb protractor. The spindle hole is very snug and the protractor itself is quite brittle. Don't try to force it over a wide spindle. It will slip down, but won't come off. I snapped mine that way. It is cheap and does work well, though.
Thank you for both suggestions. Now, to choose one.

On another note: I looked at the ven den hul website and it offers a "non-magnetic screwdriver". Is such a thing really important? If so, does anybody ever wear a static wrist strap like you wear when working on a computer? Or am I going to far with this?
Yes there's a good reason for the non-FERROUS screwdriver. The magnets in a MC cart. are pretty strong, and could attract the shank of a ferrous (iron or steel) screwdriver toward the cartridge with enough force to (if you're not paying attention) hit and damage the cantilever (oops!) or worse, if it happens to be a naked cartridge.