Plastic drums with a screw lid green are made of HDPE (high density polyethylene) with food certificate. So this plastic barrel can be used for both rainwater and leaven. The material from which the barrels are made...
Automatic 25~55%RH at ambient temperature
Totally silent operation, no moving parts
Maintenance free, self-regenerative drying agent
Minimal electricity consumption, Hygrometer does not use batteries/electricity