Tests for voltage from 100V to 600V AC.
1. Light & sound indications:
Low gear(L): red light glows once and one beep;
Medium gear(M): green light glows twice and two beep;
High gear(H): orange light glows three times and three beeps.
2. Power off automatically and manually.
3. Over voltage category: CAT III.
4. Power supply: battery" AAA" x 2