- Joined
- Jun 21, 2011
- Messages
- 507
- Reaction score
- 324
- Location
- Mills County, TX
- My Car
- 66 Mustang 347/C4
69 Cougar XR7 460/C6
Wow. I am stumped. As a WAG I would say it's for measuring the fluid in a non cylindrical container.I've had this old ruler for many years. Scale doesn't match imperial or metric measurements. Possibly and engineering scale?
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