1. Digital insulation resistance tester, with a 64x44mm LCD display, the maximum display is "1999". 2. Wide measuring range, with overrange indication, only the highest digit displays "1" when over limit. 3. With data retention function, support test lock, stable performance and convenient operation. 4. Support automatic shutdown function (about 15 minutes after booting) to save battery power. 5. Suitable for insulation resistance testing of motors, cables, electromechanical equipment, telecommunications equipment, power facilities, etc.