Aquatop Submersible Glass Heater Submersible Fish Tank Heater - 50 Watt – Pet Life
QPH-50 50-Watt Quartz Platinum Heater | Aquatop
Heaters — Corals Unlimited
Aquatop 50W Premier Glass Heater with Protective Guard - Fully Submersible for Fish Tanks Up to 13 Gallons, 68-93F Adjustable Temperature Range, Fresh & Saltwater Use, Aquarium Heaters, HTG-50 - Amazon.com