Pack Size: 10 Indicators
Thermax® 5-Level Clock Temperature Labels provide fast, accurate and permanent indication that a surface has exceeded specific temperature thresholds. Each of the five circular cells darkens irreversibly once its rated temperature has been reached, giving a reliable visual record ideal for process monitoring, quality checks, and equipment diagnostics.
Key Features
- Five irreversible temperature cells per clock
- Permanent colour change – cannot be reset or tampered with
- Circular design ideal for compact or curved surfaces
- Self-adhesive backing for quick application
- Suitable for a wide range of industrial and laboratory uses
- Supplied in packs of 10 indicators
How They Work
Each temperature point contains a calibrated heat-sensitive element that melts and migrates at its activation temperature. When exceeded, the cell permanently darkens, leaving a clear visual record that the threshold has been reached. This makes Thermax Clock indicators ideal for audit trails, maintenance, validation testing, and process verification.
Technical Specifications
| Brand |
SpotSee® |
| Product Family |
Thermax 5-Level Clock |
| Type |
Circular irreversible temperature indicator |
| Format |
5-level clock strip |
| Activation |
Cells permanently darken when temperature is exceeded |
| Temperature Units |
°C and °F |
| Pack Size |
10 indicators |
| Size |
0.55” diameter (14mm) |
| Adhesive |
Pressure-sensitive self-adhesive |
Temperature Options (Ranges 1–8)
The following temperature sets are available. Each clock contains all five temperature points listed in its range.
| Range |
°C Points |
°F Points |
| Range 1 |
40, 43, 46, 49, 54 |
105, 110, 115, 120, 130 |
| Range 2 |
60, 65, 71, 77, 82 |
140, 150, 160, 170, 180 |
| Range 3 |
88, 93, 99, 104, 110 |
190, 200, 210, 220, 230 |
| Range 4 |
116, 121, 127, 132, 138 |
240, 250, 260, 270, 280 |
| Range 5 |
143, 149, 154, 160, 166 |
290, 300, 310, 320, 330 |
| Range 6 |
171, 177, 182, 188, 193 |
340, 350, 360, 370, 380 |
| Range 7 |
199, 204, 210, 216, 224 |
390, 400, 410, 420, 435 |
| Range 8 |
232, 241, 249, 254, 260 |
450, 465, 480, 490, 500 |
Select the required range from the dropdown above. All indicators are single-use and provide a permanent record of peak temperature exposure.
Stock & Availability
Ranges shown as In stock are held in the UK. Ranges shown as Special order are ordered in from SpotSee and dispatched in about 4 weeks. The status for each range is shown when you select it. Higher temperature variants may have longer lead times depending on global SpotSee production schedules.
All Thermax indicators supplied by Stuck For® (a brand of Good Life Innovations Ltd) are genuine SpotSee® products sourced through authorised channels.