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Concise No. 270 N

• Type: Circular
• Size: 4 Inches / 10 cm
• Material: Plastic
• Scales:
  • Front: A D / C CI B K L
  • Back: DI D / S T₁ T₂ ST

With vinyl case. Front and rear disks slide independently. Slide circles set flush to body. D scale runs clockwise on each side, with indexes aligned. Thus flipping the rule gives a reciprocal on the reverse D scale or the original number on the DI scale. Index of S scale reads "90". There's plenty of room in the center of the reverse for your corporate logo. Obtained from Concise in January 2006.

Instructions, side 1
Instructions, side 2