Vintage Spies Hecker Metal Auto Paint Mixing Rulers - 2

Vintage Spies Hecker metal auto paint rulers. Marked MS System. Spies is a specialized paint company, so these may have been used for mixing values. One side says 4 to 1 and the other side 2 to 1. Preowned condition. Some paint residue on them. Measures 1-1/8" wide and 13-3/4" long.