The clock tells the time-of-day to the second and shows temperatures from ‚Äì4 to 104°F and ‚Äì20 to 40°C with ¬±1.5°C accuracy. O-ring sealed waterproof/dustproof ABS plastic impact-resistant case makes it ideal for wash-down areas, outdoors, and nasty environments. Quartz-crystal accuracy is 0.01%. Modern style clock and bright blue sweeping second hand may be read at fifteen feet. To assure accuracy an individually serial-numbered Traceable® Certificate is provided from the manufacturer's ISO 17025 calibration laboratory accredited by A2LA. It indicates traceability to standards provided by NIST (National Institute of Standards and Technology). Case diameter is 7 inches, dial diameter is 5 inches, and weight is 12 ounces. AA battery, wall-mount, and screw are included. Replacement battery Cat. No. CON1111.