| Name | Keuffel & Esser < 4138 > S Morrison Radio Engineer's Slide Rule |
| Front Scales | (F left) L F A = B CI C = D T ST S (F Rt) db FREQ LC = = (Back left) 9 8 = 7 6 5 4 = 3 2 1 (Back right) Att. Factor II Att. Factor I = d,Miles Cd P,Watts f,Mc = (sigma),emu E,microw |
| Back Scales | |
| Type of Rule | |
| Material | Engine divided celluloid laminated mahogany |
| Dimension (mm) | |
| Area of Use | |
| Origin of Rule | Michael O'Leary |
| Match Number | 4428 |
| Comment | |
| Thumbnail | No Picture |