| Name | Keuffel & Esser < 4088 - 3 > Polyphase Duplex, dated 1913 |
| Front Scales | K A = S T CI = D L |
| Back Scales | DF = CF CIF C = D |
| Type of Rule | slide rule |
| Material | Engine divided celluloid laminated mahogany |
| Dimension (mm) | |
| Area of Use | generic |
| Origin of Rule | Bob Otnes |
| Match Number | 4300 |
| Comment | |
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