ST-3 Mini Aquarium Thermometer with Suction Cup, Electronic Aquarium Probe, Temperature Display (50–70 °C), Digital Display, Waterproof Probe--DTEKGAZ

Screen dimensions: 58 mm (L), 36 mm (W), 11 mm (D); Probe cable length: approx. 90 cm; Temperature measuring range: -50 °C to 60 °C; Accuracy: ±1 °C; Ambient temperature: -10 °C to 50 °C; Battery: 1.5 V button cell (LR44); Instructions: 1. Attach the screen outside the aquarium (the screen must not touch the water) and immerse the probe. 2. Press the power button to display the temperature. To turn off the device, press and hold the power button for 3 seconds. 3. The screen displays "HC" for temperatures above 70 °C and "LC" for temperatures below -50 °C.