Conventional wet liquid. Maintenance Free. Deep Cycle – Golf Car, Marine, Solar. SLA / VRLA – AGM & GEL. Any size battery from U-1 up to 8-D. Charges up to 4 batteries at one time. It’s a Battery Maintainer: Can be left on for months at a time. Will not damage your battery. Your battery will be ready when you are. It’s a Battery Conditioner: Sulfation is the # 1 cause of battery failure. Battery MINDer generates a resonant pulse current to breakdown the lead sulfate crystals. U.S. Pat Pend. #60-083,473. Works on all types of 12 volt batteries. Unit comes complete with the following: Qwik Connect with Clips & Ring Terminals. Hydrometer type battery tester. 12 ft. output cord.