The REOTEMP K83W Worm Therm worm composting thermometer is made specifically for vermicomposting. We worked with worm composting experts to develop the highlighted range on the dial and the included digital guide for worm composting (vermicomposting). Just keep your worms in the highlighted green range on the dial to maximize vermicompost production and worm reproduction. The Worm Therm is a high quality thermometer that is waterproof and dustproof, perfect for monitoring worm temperature. The worm therm is user calibratable with a turn of the calibration screw on the back of the head.