Quickly check a vehicle's charge system status through an OptiMate SAE to 12 V socket adapter Monitor by the use of (4) blinking LED lights. 

Features

• (4) LEDs blink every three seconds to indicate a batteries state-of-charge 
• Automatic 2-mode Operation
  • Storage: Displays battery voltage from empty to full including higher-voltage AGM batteries (12.7 V) with long term amp draw less than 0.2 mA
  • Engine Running: LED arrow mode activates when the minimum of 13.5 charge volts is reached
• Integrated 2-pin SAE quick-connect charging port for an easy charger hook-up with rubber sealing cap
• Compatible with 12 V lead-acid AGM, GEL, or STD batteries
• Fits standard 7/8 in. (21 mm) 12 V power socket that remains hot when the ignition switch is turned off
• 10 Amp fuse for protection integrated inside the connector
• 18 AWG cable
• Works at -40 degree Fahrenheit