Three-Speed Battery Operated Hygrothermograph (No. 49439) includes everything you need to get started: two felt-tip pens (one blue, one red) and a roll of one-month paper. Allows you to choose from one, seven or 32-day operation with the flip of a switch. Works well in indoor or sheltered outdoor environments such as storage or agriculture areas. Features single-button battery condition tester and flashing LED which indicates that unit is operational. Runs on two C batteries (included) for up to six months. 13-1/4"H x 5-1/8"W x 11-1/2"L.
Economy Mini-Drum Hygrothermograph (No. 89292) is an inexpensive, compact drum chart recorder with high accuracy and consistent readings. Features a built-in LCD clock in base—allows you to view time at a glance. Corrosion-resistant acrylic housing for indoor or sheltered outdoor use. Includes 55 sheets of seven-day, °C chart paper.