Tetra HT 50 fully electronic aquarium heater for an aquarium size of 25-60 litres. With 3-stage status LED for an easy to read and user-friendly temperature setting. Temperature adjustment knob for selecting the desired water temperature in the range of 20 °C to 32 °C in increments of 1 °C. Waterproof cap, i.e. fully immersible, secure attachment via two suction cups, extra thick heat-resistant and shock-resistant borosilicate glass tube. Fully electronic and with integrated microprocessor for high precision and operating accuracy/control light for the heating phase. Long power cord (1.6 m) for easy installation in the aquarium. Additional safety shut-off to protect against burns