"Battery Tender DVS - 20 Heavy - Duty Fast Chargers... fast, effective Chargers you can count on in a jam. Click image to enlarge... These portable Chargers have been servicing the marine industry for years, and are ready to power up and maintain your boat battery's strength. Employ a maximum power output of 300 watts out of your 12-volt output with a 40 amp current. Features a variety of software configurations to suit your needs: DELCO, standard, seals, VRLA, GRT, AGM and GEL. You'll appreciate the status indicator lights that keep you abreast of the charging status: Solid Green means the charger is ready to begin charging the battery; Solid Red means your battery is charging normally; Flashing Red means the charger is experiencing an abnormal condition and Flashing Green means the charge is complete. All Chargers come with jumper cable-type harnesses with heavy-duty alligator clamps. Has short-circuit and reverse polarity protection for your safety. Choose between a Single-Sealed AGM and Standard Charger. S"