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Pickett N 600-ES Log Log Speed Rule

• Type: Log Log Duplex
• Size: 6 Inches
• Material: Aluminum
• Scales:
  • Front: +LL1 -LL1 A [ B ST T S C ] D DI K
  • Back: +LL2 -LL2 CF [ DF Ln L CI C ] D +LL3 -LL3
• HvH: 2172

Low-glare yellow base color. brown, leather case with pocket clip and quick-extraction tab. Functionally identical to the N 500 above except for Natural Log Ln scale inplace of CIF. Gift of Gretchen Apgar.

I don't have such a set myself, but I've learned that they sold this and the 500 together as a complete set, one for the office, one to travel with. Logical, they have the same scales. Like the katana and wakazashi of the samurai, two rules are better than one.

This model was on the manifest for several Apollo missions as a backup computer. Imagine!