Standard Insulation Tester ST 5500
The ST-5500 has many features such as 250V, 500V, or 1000V test voltage combinations, a large, easy-to-read dual display with a backlight, and a durable double molded plastic housing making it stand up to the test of time. With its CAT III 1000V rating, this is the only insulation tester you need in your tool bag.