IDEAL® Insulation Tester, Battery Operated, Series: 797, 0.1 to 600 VAC/VDC, 4 MOhm to 20 GOhm, 73 deg F +/-41 deg F (23 deg +/-5 deg C), < 70% R.H Accuracy, 4000 Count Display, Safety Rating: CAT IV 600 V, After 20 min of Non-Use Auto Power Off, AA LR6 Battery, 8.1 in L x 3.7 in W x 2 in H