B.T.U. Rule Co. B.T.U. Rule for Estimating Steam or Water Radiation

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Country of manufacture: USA,            Date of manufacture: ____
Overall length: 33.5 cm,          Width: 4.6 cm,           Weight: 118.5 gms
Materials: Plastic printed scales attached to wooden body with screws
Cursor: __ X __ X __ cms; MISSING; lines = ___
Scales: 5, specialized
Front: Steam Radiation [ Contents in Cubic Feet, Glass in Square Feet, Wall in Square Feet ] Water Radiation
Back: Instructions for Use
Slides: Two slides, faces A/B, and C/D; used as described on back of rule.
Condition: C5 (signs of normal use but missing cursor)
Came with: Original labeled cardboard box

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