Easy to use charger that is packed with features. Our advanced 40A Automatic Portable Battery Charger harnesses high frequency technology and automatically delivers three-stage charging for your AGM or flooded starting or deep-cycle battery. An easy to read digital LCD screen displays charging and battery status with intuitive icons, and features a patented Alternator Check to indicate if the alternator is maintaining battery level. The Engine Start Timer gets you back on the water (or the road) quickly. Its simple to use and easy to store with cable wrap and clamp storage built in. Key Features 40 amp Fully Automatic Charger Compatible with AGM and flooded 12 volt batteries Fully Automatic high frequency chargingto deliver 3 charging stages 110 amp Engine Start feature allows re-start most vehicles in up to 90 seconds. Patented alternator check and battery voltage check confirms alternator is properly maintaining battery Battery reconditioning feature helps extend battery life Reverse polarity protection LCD Screen with easy to read icons AC Low-voltage compensation ensures maximum performance when used with extension cords Dimensions: 15 7/8"W x 5 3/8"H x 9 7/8"DOwner's Manual