500W Automatic Aquarium Heater with LED Digital Display Variable Frequency IPX6 Waterproof Fish black

500W Automatic Aquarium Heater with LED Digital Display Variable Frequency IPX6 Waterproof Fish black.Feature: 1. Variable Frequency: PID temperature control algorithm, realizing high heat and low power consumption, using intelligent frequency conversion technology, the power size is freely adjusted by the chip, soft temperature control. 2. Fast Heating: Selected silicon carbide sand filling, safe and stable, fast heat conduction, energy saving and power saving, high purity nitinol wire, thicken