Optimate Monitor O-124, Permanent Power Sport Battery Lead with Integrated Battery Status/Charge System Monitor for 12V Lead-Acid. Monitor charge of your stored power sport vehicle 12V lead-acid battery or confirm if the vehicle charging system is working correctly! 4 LEDs cover full to empty voltage range of all 12V batteries, including higher voltage AGM for power sport (4th  LED  12.7V ). 2 automatic Modes  Battery charge level monitor (single LED blink mode) & Charging system test (arrow mode). Model O-124 specs: L= 24 / 60cm, 15A fuse, 1/4 / M6 ringlets; 16AWG cable SAE charge port with weatherproof sealing cap.