FEATURES: Adjustable, precision duct-mounted humidistats allow the units to be set for optimum relative humidity Convenient orientation allows right or left-side panel for easy installation and easy access in the future Single screw secures cover 2" evaporator pad expands the evaporative area for water supply and increases performance Cleanable/replaceable internal water filter protects solenoid Self-piercing saddle valve and a 24V brass solenoid valve makes installation easy G200 mounts on 10" duct, G300 mounts on 141/2" duct Wide 11/2" collar for ease of installation HOW HERRMIDIFIER HUMIDIFIERS WORK: Evaporative humidifier is installed onto the supply duct, where warm, dry air is forced across a moistened evaporator pad (wetted through the home's water supply), creating a superfine mist that is released into the indoor air.The adjustable, precision made humidistat allows the user to choose the optimum level of relative humidity for indoor comfort.