Adjustable
- Mercury-in-glass type; immersion depth 76 mm
- Can be quickly and easily set by rotating annular magnet in cap, which drives tungsten contact wire; 10-division reference scale on cap aids in fine adjustments
- Accuracy ±0.01°C
- With two temperature scales
- Yellow-back scale at bottom indicates operating temperature; white-back scale at top used to set desired operating temperature
- For use with relays having maximum 30 milliampere, non-inductive contact load
Overall length 390 mm; length of glass part 305 mm; upper diameter of glass part 19 mm tapering to 7.1 mm diameter; lower 76 mm length is 7.1 mm diameter; with 1.2 meter cord with spade lug terminals for wiring to relay.
| Thomas No. | Setting Range | Divisions |
| 9366K15 | -38 to +40°C | 1°C |
| 9366K25 | 0 to 100°C | 1°C |
| 9366K35 | 0 to 200°C | 2°C |