Stainless Steel Mechanical Thermohygrometer | Battery-free · German-engineered movement | High-precision laboratory grade | Wall-mounted or desktop | Suitable for home, nurseries, warehouses, pharmacies and fridges

Say goodbye to battery anxiety and return to physical precision.
Featuring a German-patented movement and a one-piece stainless steel body formed under 50 tonnes of pressure, it accurately detects changes in temperature and humidity. Whether for temperature control in a nursery, data logging in a laboratory, or monitoring a cigar humidor or warehouse, the TH603-L is your reliable physical indicator.

Are you looking for a battery-free, permanently powered thermometer and hygrometer? The TH603-L utilises a purely mechanical drive and features a proprietary temperature and humidity regulation mechanism. Not only can it withstand extreme temperatures ranging from -30°C to 60°C, but it also maintains a high precision of ±5%RH within the core humidity range (40%–70%RH). Its 430 stainless steel body and thickened high-definition glass are designed specifically for users seeking precision and durability, making it an ideal choice for domestic, industrial and research applications.

✅ Detailed Specifications 
Dial Diameter: 127mm (12.7cm)
Body Thickness: 21mm (2.1cm)
Net Weight: 250g
Materials and Craftsmanship: 430 stainless steel (single-piece stamped), thickened flat transparent glass, copper movement
Temperature Range: -30°C to 60°C (Measurement Accuracy: ±1°C)
Humidity range: 0% to 100% RH
High-precision range (40%–70% RH): Accuracy ±5% RH
Other ranges: Accuracy ±7% RH
Mounting method: Detachable base (suitable for desktop placement or wall mounting)
Power supply: No batteries required (mechanically driven / perpetual power)

1. Lifetime battery-free | German-engineered movement
Say goodbye to the hassle of changing batteries. Equipped with a German-patented movement, it utilises pure physical sensing and mechanical drive. Whether during a power cut or in extremely cold conditions, the TH603-L continues to operate stably, ensuring truly uninterrupted power.

2. 50-tonne Pressure One-Piece Moulding | 430 Stainless Steel Body
A single piece of 430 stainless steel is precision-stamped under 50 tonnes of pressure, resulting in a structurally precise and robust design. Not only does this provide excellent sealing to protect the internal movement, but it also delivers a finely crafted metallic finish that enhances the aesthetic of any home.

3. High-Transparency Glass & Dynamically Balanced Hands
Fitted with thickened, high-definition flat glass, it offers high light transmittance and scratch resistance. The dial markings are clear (visible from a distance of two metres), paired with a dynamically balanced pointer to minimise friction errors, ensuring every reading is precise and reliable.

4. Flexible Installation: Dual-Purpose Design
Desktop Placement: Equipped with a removable square base for stable placement, serving as both a practical tool and a decorative piece.

Wall-Mount Mode: The rear features a 10mm diameter gourd-shaped mounting hole for easy installation on walls, wardrobes or the side of a fridge.

5. Proprietary Temperature and Humidity Adjustment Mechanism | Calibration Support
The product undergoes rigorous calibration before leaving the factory (no secondary calibration required).

Temperature calibration port on the front
Humidity calibration port on the back
The built-in adjustment mechanism ensures precise fine-tuning even when the device is sent for metrological testing or used for scientific data logging, guaranteeing long-term data accuracy.

🎯 Suitable Scenarios
【Northern/Cold Regions】: Monitors indoor heating temperature and dryness during winter to prevent ‘frostbite’ and ‘overheating’.
【Southern/Coastal Regions】： Real-time monitoring of humidity fluctuations during the ‘return of the south wind’ season to prevent mould on clothing and furniture.
【Nurseries/Maternity Rooms】： Providing a comfortable temperature zone for newborns (recommended temperature 20–26°C, humidity 50–60%) to ensure a peaceful sleep for your baby.
【Cigar/Tea/Wine Cabinets】： Meeting the stringent humidity requirements for the storage of specialist collections.
【Laboratories/Warehouses/Greenhouses】： With robust mechanical stability, this device is suitable for environments requiring long-term, stable monitoring.

⚠️ Important Note
This product is a mechanical analogue thermometer and hygrometer. Compared to digital displays, analogue readings offer a more vintage aesthetic and are not affected by the ageing of electronic components. Should you notice a slight discrepancy, you may fine-tune the reading via the calibration hole on the body of the device.