The PS200 is a 12-Vdc battery with a charge controller. The controller manages amperage and voltage for safe, optimized battery charging from a solar-panel or AC power source. It also measures various input, output, and status parameters to allow close monitoring of the battery during charging and use. The PS200 includes a 12-Vdc lead-acid battery, while the CH200 is for use with a user-supplied battery. Note: If you do not need or desire the 6182 7 Ah Sealed Rechargeable Battery that is shipped with the PS200, consider ordering the 22238 instead.