This series of programmable constant temperature and humidity testers are also known as high temperature and humidity alternating testers or constant temperature baths. They are mainly used to simulate the harsh high temperature or humidity environment that electronic instruments, new materials, electrical engineering, vehicles, metals, electronic products, aerospace materials, etc. may encounter during transportation, storage, and use; or to test the high temperature and humidity resistance of materials, accessories, or instruments and equipment in a high temperature and humidity alternating environment, as well as the possible damage and shortened lifespan.