Features Purpose: This battery tester is used to start a lead-acid battery and check the following conditions of the battery, starting, charging and loading. Easy to operate: The tester is exquisite in design, easy to operate, accurate in readings, and complete in functions. Display data: It provides readings on the large LCD display and passes sound and light prompts during testing. Data collection: It uses the 4-wire Kelvin method to complete a series of complex data collection, thereby calculating each test data through the built-in precision circuit and an improved digital processor. Safety protection: Some improvements have been made to the circuit, including polarity reversal protection, over voltage input protection, and loose lead detection to ensure safety and convenience during testing. 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 Battery tester size: 12 * 5.2 * 1.8cm / 4.7 * 2 * 0.7in Features: Portable Functions: Improve driving safety Material : Plastic, Copper Color : Gray Package List: 1 x 12V Digital Battery Alternator Tester 6 LED Lights: Alternator state check: First light (red): Fault Second light (green): Good Third light (green): Full Battery state check: First light (yellow): Middle Second light (red): Low Third light (green): OK