The calibratable humidity-temperature sensor for outdoor installation HYGRASGARD® AFF ⁄ AFTF (± 2.0 %) and AFF - 20 ⁄ AFTF - 20 (± 1.8 %) with plastic sinter filter (metal sinter filter optional) or AFF - 25 ⁄ AFTF - 25 (± 1.8 %) with metal sinter filter with plug-in measuring head, housing made of impact-resistant plastic, optionally with ⁄ without display. It measures relative humidity and / or temperature and converts the measured variable into a standard signal of 0 -10 V or 4...20 mA. It has four switchable temperature ranges and is used in non-aggressive, dust-free environments in refrigeration, air conditioning, ventilation and clean room technology.