| Name | Keuffel & Esser < 4054 > Polyphase (Mannheim) |
| Front Scales | A = B CI C = D K |
| Back Scales | = S L T = |
| Type of Rule | slide rule |
| Material | Engine divided celluloid laminated mahogany |
| Dimension (mm) | |
| Area of Use | generic |
| Origin of Rule | Michael O'Leary |
| Match Number | 4145 |
| Comment | |
| Thumbnail |  |