The FJC 45110 100 AMP Battery Tester provides a quick and reliable way to check 6- and 12-volt batteries. Designed for automotive applications, it tests battery current draw, voltage, and alternator performance with a simple 10-second load test. The 100 AMP tester helps technicians quickly identify battery and charging system issues, making it a practical tool for routine electrical system checks on cars, trucks, and other 6- and 12-volt applications.