| Name | Keuffel & Esser < 4088 - 3 > Polyphase Duplex |
| 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) | 308x30.4x6.6 |
| Area of Use | generic |
| Origin of Rule | Michael O'Leary |
| Match Number | 4301 |
| Comment | |
| Thumbnail |  |