| Name | Keuffel & Esser 68 - 1617 Polyphase |
| Front Scales | 10inch / A = B CI C = D K \ 25cm |
| Back Scales | = S L T = |
| Type of Rule | slide rule |
| Material | Engine divided celluloid laminated mahogany |
| Dimension (mm) | 277x36x8 |
| Area of Use | generic |
| Origin of Rule | Miles Schumacher |
| Match Number | 4119 |
| Comment | |
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