Features:  Preferred Mateiral: The cover is made of ABS insulation material, shockproof and can provide a long service time.  LCD screen with backlight design, you can press the button to turn on or turn off the backlight according to your needs, so you can see the testing data clear even at night.  100 Group Data Storage: After  measuring the insulation resistance value, press HOLD button to keep the data first, and the screen will appear "HOLD" symbol, and then press READ button to save the data.  Absorption Ratio (DAR): Determine whether the equipment is affected by the dampness of the insulation resistance measurement Instrument programming defaults for calculating DAR with insulation resistance values at 15 seconds and 60 seconds.  Polarization Index (PI): PI measurement is used to identify the aging of insulation quality. The insulation resistance value at 1 and 10 minutes is used to calculate PI.  Wide Applications: This tool is suitable for measuring insulation resistance of , motors, cables, switches, electrical appliances and other electrical equipment and insulation materials. Suitable for various electrical equipment maintenance, repairs, test and verification.    Specifications:  Material: ABS  Type: 1000V-20GΩ, 2500V-200GΩ (optional)  1000V-20GΩ:  50V/100V: 0.1MΩ~200MΩ  250 V: 0.4MΩ~20GΩ  500V: 1MΩ~20GΩ  1000V: 2MΩ~20GΩ  2500V-200GΩ:  250 V: 2MΩ~20GΩ  500V/1000V: 1MΩ~20GΩ  2000V: 3MΩ~200GΩ  2500V: 5MΩ~200GΩ  Voltage measurement: 10-600V  DAR: √  PI: √  Auto ranges: √  Auto shut-down: √  Data retention: √  Low voltage alert: √  Test voltage display: √  High voltage indication: √  Measure time display: √  Power: 8 * AA batteries (NOT included)  Package size: 210 * 200 * 90mm / 8.3 * 7.9 * 3.5in  Package weight: 1100g / 2.4lb    Packing list:  1 * Insulation Resistance Tester  1 * Pair Pen  2 * Clips