hygger HG-921 Smart PTC Heater User Manual
Discover the hygger HG-921 Smart PTC Heater manual with all you need to know about this aquarium heater. Featuring a rapid heating rate, dual relay design, LED digital temperature display, and external temperature controller, this heater is perfect for 60-180Gal freshwater aquariums. Keep your aquarium at the perfect temperature with this safe and accurate product.