Penn Plax Cascade 100 Watt Adjustable Heater Part # CH8100
For 20 Gallon Tank
 
Accurate to 1 °
Fully Submersible
Mount Horizontally or Vertically
Factory Preset at 76°
Temperature Dial Adjustment
Fresh or Saltwater Safe
Visible & Accurate Temperature Setting Scale
Easy View On/Off Light 
Length 8.5"