McMaster Carr has the compass in clockwise ,counter clock wise and I think 0 to 180 in both directions .Made of mylar with an adhesive back .
I've made several and gave them away .I get the tin knockers at work to cut out a piece of 10 gauge aluminum for the backer .I think my personal one is an 8 inch.
The first one I made was cut out round on the lathe ,worked .The tin knockers can spin one out in about a minute or less .--tain't what you know sometimes tis who you know .