• Made of corrosion - resistant acrylic for indoor or sheltered outdoor use
• Spring winding keeps chart running for eight days
• Even when the motor begins to run down, a steady chart speed is maintained
• Includes one 1-day gear and one 7-day gear, two felt-tipped pens (red and blue), and one 7-day rotation chart

Create permanent records of critical relative humidity, temperature, and barometric pressure data. These hygrothermographs and barographs are ideal for monitoring ambient conditions in laboratories, greenhouses, museums, libraries, and more! Each has multiple speeds so you can select how long recording runs unattended.

Battery-powered models feature a low battery indicator to ensure batteries are always fresh; spring wound model maintains an even chart speed for 8 days after winding. Each instrument has a corrosion-resistant acrylic plastic case with a locking, tinted cover for easy viewing.