A wireless hydrometer and thermometer that measures directly in the fermenter, and comminicates to the app BrewConnect via WiFi. It can be used independently in a brewing via WiFi, but the extra smart thing is that it can communicate directly with Ferminator Connect via Bluetooth. This allows a Ferminator Connect to know the exact temperature inside the beer and adjust the temperature even more precisely. The Gravity charger is charged wirelessly via the included wireless charger. It should therefore never be opened, and you avoid the risk of it leaking and destroying a brew. If the Graviator is not charged before brewing, this is not a problem. It can be charged in approx. 5 hours. The improved algorithm in Graviator, the unique design and build quality provide a high accuracy of ± 0.002 SG. The size and weight of the engraver also make it more stable under the crotch.Please observe! The Graviator does not work with steel fermenters.