From Hanna , HI 8564 thermo-hygrometer provides readings with high precision in a very short time for both R.H. and temperature.
The detachable R.H. probe is housed in a rugged ABS cylinder with a thin-film polymer humidity sensor and a signal amplifier. A perforated cap on the probe allows the air to circulate while it protects the sensor. The standard cable is 2 m long (7'), and a 5 m (16.5') version is also available. HI 8564 is specially designed for controlled environment applications such as museums, libraries, computer rooms and printing facilities. The smooth membrane keyboard has 4 keys that make operation simple and quick. A large LCD displays readings in easy-to-read digits each with a symbol next to it to identify the operating mode.
HI 8564 is supplied complete with HI 70601/2 RH probe with internal temperature sensor and 2 m cable, battery and instructions.