This is the Largest of the Sentinel dehumidifiers, the Sentinel HDi120 Dehumidifier which we use in conjunction with our Air movers as part of our Drying room System, It hads a digital hydrostat so turns on when there is high Relative Humidity and off into a standby mode when the correct Humidity is reached. This ensures only as much power is used to dry the kit, making drying very energy efficient. It also has a condensate pump allowing the dehumidified water to be pumped away easily.