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Details and Image
Type
Model No.
Maker
Country
Construction
Material
Date
Scale Length
Area of Use
Linear
Ballantine Rule
Perrygraf for Ballentine Laboratories
USA
Cardstock
c. 1953
7.6 cm x 21.3 cm
Electronics Industry
Notes:
Used to calculate simple electronic conversions and ratios.
Image 1
Image 2
