STANDARD FEATURES found on both Vivarium Electronics VE-100 and VE-300 Thermostats include; 1) a 700 watt capacity with user-replaceable fuse protection from power surges, 2) displays probe temp, set point and current time on full back-lit display, 3) remembers settings after power interruption, 4) a 10′ probe cord, 5) grounded receptacle designed for outlet strip use, 6) safety backup relay shutoff cuts all output power if the probe temperature reading rises more than 6 degrees above the set point, 7) silent operation, 9) convenient table top mounting, 10) multiple units can stack for neat, professional appearance. FEATURES SPECIFIC to the Vivarium Electronics VE-100 Thermostat include; 1) On/Off style thermostat operation, 2) “Night Drop” capability with the purchase of an additional “ND (night drop) Module”. The Vivarium Electronics VE-100 Thermostat is a “table top” model designed to sit nicely on top of your racks or cages. A 3-button keyboard makes it ultra-easy to navigate through the menu and the large back-lit display makes programming easy and intuitive. WHAT IS A ON/OFF STYLE THERMOSTAT? Basic on/off thermostats will simply turn off the device when the set temperature is exceeded, then turn it back on when the temperature has dropped below the set temperature. This means they have a 1 to 2 degree “slop” (or more in cheaper ones). Therefore, if you set your thermostat at 80 degrees, your actual temps can vary between as low as 76-78 degrees and as high as 82-84 degrees. WHAT IS A PROPORTIONAL STYLE THERMOSTAT? Similar to an on/off style thermostat, a proportional thermostat has a probe that tells it when heat needs to be turned “on” or turned “off”. Unlike an on/off style thermostat, a proportional thermostat also works like a dimmer in that it can adjust the amount of voltage being applied to the heating device.