Specifications Range: .. to 1990 uS/cm Resolution: 0.1mS/cm Accuracy: ±1 % full scale (±2 % above 10mS/cm) Calibration points: 1 (digital, push-button) ATC: Yes Non-Volatilememory: Yes Hold Function: Yes Auto-Off: 8.5mins after last key pressed LCD Display: 3 ½ digit with annunciator Power: 4 X 1.5 V 'A76'micro alkaline batteries Ingress Rating: IP67 Waterproof Dimensions; Weight: Boxed: 24.5 cm x 13.5 cm x 4.5 cm; 137 g