ANCEL battery tester works with 12V and 24V batteries and provides 99% measurement accuracy. This professional tester measures maximum load, resistance, starting power, and overall battery performance. Readings are instant and displayed on a small screen with bright backlighting for night work. It is compatible with various battery types, including EFB, AGM, and gel batteries. Activation requires connecting the device to the terminals using special clamps. Built-in protection guards against reverse polarity, short circuits, and overheating. A unique feature is the integrated mini-printer, which immediately prints out test results on paper.