The Model 616 is ideal whenever temperature monitoring is required. It is available in various temperature ranges and time periods. Applications include: transportation of perishable goods, walk-in freezers and refrigerators, shipping containers, cold rooms, dairies, drying sheds, greenhouses, and buildings such as hospitals, schools, and offices.

This thermometer uses a spring-wound chart drive and will operate in extreme temperatures (from -40°F to +240°F) where batteries fail. One full winding is enough to drive the chart well beyond its full recording range, whether 24-hour or 7-day.The clock motor has been electronically timed for accuracy and has been test run through its range to ensure reliability. Jeweled clock bearings for the escapement are standard on this unit.

The bimetal sensor is made of ASTM specified TM2 alloy, and will normally retain its calibration for the life of the instrument. The stainless steel stylus never needs sharpening or replacing. The 3-5/8 inch diameter paper charts are pressure sensitive and plastic coated in white. Time and temperature graduations are printed in blue. The stylus scribes a permanent temperature-time trace in black.