| Name | Graphoplex 691 a Neperlog Hyperbolic Variant |
| Front Scales | L P K A = B T ctg ST S cos = D Th Sh2 Sh1 |
| Back Scales | LL01 LL02 LL03 DF = CF CIF CI C = D LL3 LL2 LL1 |
| Type of Rule | slide rule |
| Material | plastic |
| Dimension (mm) | 338x48.7x4.2 |
| Area of Use | generic |
| Origin of Rule | description/copy |
| Match Number | 2998 |
| Comment | |
| Thumbnail | No Picture |