LED display indicates condition, for 12V battery only. Alternator state check, battery state check, check before charge and overload display. Alternator check: accelerate your engine to 2000 rpm when the green light is lit ,charging circuit is ok. Battery check: indicate the percentage charging in the battery . Charger check: when green light is lit, charging is complete. LED display indicates condition Check before Charge: Battery is alive, "OK" to be . and Multiple functions: alternator state check, battery state check, check before charge and overload display. 6-LED display, clearly present the alternator and battery state. Two testing clips for safe and easy operation. Small size and light weight, convenient to carry. Fit car, motorcycle, etc., with 12V battery. Specification: LED quantity: 6 (2 red, 3 green and 1 yellow) Material of wire: 0.06square millimeter copper Max. voltage and current: 12V 15A Length of wire: 25cm / 9.84in colour: black Material: ABS size: Battery tester size: 12 x 5.2 x 1.8cm / 4.7 x 2 x 0.7inch Package Contents: 1 x Battery Tester with Two Clips Only the above package content, other products are not included. Note: Light and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is 1-3cm.