General Technologies introduces the CT8007 Polarity Circuit Tester. This computer-safe, all-solid-state circuit tester is designed for use with any DC powered circuit from 3V to 28V. A high-impedance circuit tester, this tool is safe to use around automotive computeres, electronics and air bags. The CT8007 is self-powered (no batteries needed) and requires no wire or clip connector to ground. The LCD display shows polarity, allowing users to check for power and ground in less time that it takes to set-up a regular test light.