USD $15
The Sterling “Add-It” machine uses an included stylus to allow a user to add and subtract. Usage directions printed on the front of the device.
Stock: 1
USD $35
12″ / 10″ Simplex Mannheim Trig Slide Rule
Embossed white plastic construction, black scales. A very useful and popular student rule, from the last production of the Sterling/Acumath/Borden Plastics amalgamation. They are great as a first student rule, and come in the original box, with a plastic slip case, and instruction manual.
(9 Scales)
Front – S, K, A, [ B, CI, C ] D, L, T
Stock: 2
Sphere Research Corporation