Tu 1 cup, Tu 4 cups, ISO outFlow Cup, and Ford Viscosity Cup have different reference ranges for standard material selection, as shown in the following table:
| Viscometer | temperature °C | Outflow time s | Standard material reference viscosity mm2 s-1 | |
| model | Specification | |||
| Tu-1 | / | 0-50 | >20 | >358 |
| Tu-4 | / | 0-50 | <23 | <78 |
| 0-50 | 23≤t<150 | 77-645 | ||
| Portable TU-4 | / | 0-50 | <23 | <78 |
| 0-50 | 23≤t<150 | 77-645 | ||
| ISO series | 3 | 20-30 | 30-100 | 7-42 |
| 4 | 20-30 | 30-100 | 35-135 | |
| 5 | 20-30 | 30-100 | 92-325 | |
| 6 | 20-30 | 30-100 | 188-684 | |
| Ford series | 1 | 19-27 | 55-100 | 10-31 |
| 2 | 19-27 | 40-100 | 32-118 | |
| 3 | 19-27 | 30-100 | 55-215 | |
| 4 | 19-27 | 30-100 | 99-367 | |
| 5 | 19-27 | 30-100 | 339-1185 | |
