| Manufacturer | Concise Co. Ltd. |
| Model | No. 28, customized for Otis Engineering Corporation |
| Serial No. | |
| Overall diameter | 8.2 cm |
| Body/Slide materials | Plastic |
| Post materials | |
| Cursor materials | Plastic |
| Scales | D [C CI A K] "Gas Table" "Fluid Weight Conversion Table" |
| Accessories | Black vinyl case labeled "Otis Engineering Corporation" and "Concise" |
| Notes | |
| Tag No. | CON-28-OTIS |
