The Hatch Box is equipped with a thermometer that allows you to monitor the temperature of the reptile eggs at any time. This measure not the temperature in the incubator or the average temperature, but the temperature of the eggs themself.
The real difference with other incubation boxes however, is the substrate-free incubation method. This is not only very hygienic, but also prevents a moulding of the eggs. Lucky Reptile states that by incubating over water (the box consists of an egg insert over a shallow bowl filled with water) there is a steady and sufficiently high humidity.