D’Addario Humiditrak® is a tiny sensor the size of a key fob which allows you, without opening the case, to check the microclimate within via your smartphone (not included), and monitor it graphically by hour, by day and by month. 21-day memory. The sensor can alert you if preset parameters are exceeded. 1-year battery life, range up to 50’. Includes motion sensor.
Added weight is 15g.