Outside wall resistance thermometer ⁄ weather sensor THERMASGARD® ATF-01 with passive output, enclosure made of impact-resistant plastic wit snap-on-lid for the detection of outside temperatures, temperatures in wet room areas, e.g. as weather sensor for installation on outside walls, in cold storage buildings and greenhouses, in halls, in the industrial sector and in agriculture. Installation in outdoor areas preferably at the north side of a building or in a protected place. In case of direct solar radiation, a sunshade protector SS-01 should be used.