vintage Bruning 12" plastic drafting machine rule

Description

Good morning all. Here is a vintage Bruning 12" plastic drafting machine rule. One side is graduated in 32nds. The other side is graduated in some scale that I don't have the brainpower to figure out (see 2nd picture at bottom). The rule is flat. You can see the aluminum attachment pieces in the pictures. The bolts are all nice - no slippage marks in the slots. The little "U" pieces are steel.
In terms of condition, PLEASE NOTE:
1. The markings are faint. They actually look better in the pictures than in person.
2. There are 2 chips in the rule. One is at the end (8th picture), so it does not impact anything much. The other is in the back, on the side with the unknown scale, about 3/16" long, at about the 3-1/4" inch mark. The chip impacts the bottom of the side, but not the top of the rule (the last 2 pictures explain it better than I just did).