Magnum Energy MS4024PAE MS-PAE Series 4000W 24VDC Pure Sine Inverter/105 Amp PFC Charger/120V-240V Input/Output, Power Factor Corrected (PFC) Charger, Safe and reliable, Versatile mounting, Multiple ports, Convenient switches Power Factor Corrected (PFC) Charger: Our PFC charger is built into all of our inverter chargers. It uses less energy from a generator than a standard charger  using 25-30% less AC current than standard chargers No series stacking required: The unique design of the MS-PAE Series can provide 120 and 240 volts output in one unit, eliminating the need to stack two units together to get 240 volts Parallel stacking: You can parallel up to four inverter / chargers for up to 17.6kw of power at 120/240V. The MP panels and router are required for parallel stacking the MS-PAE Series Safe and reliable: The MS-PAE Series is ETL Listed to the stringent requirements of UL 1741, 1st edition, and CSA C22.2 #107.1-01 for renewable energy installations Pure sine wave: Power your T.V.s, stereos, plasma screens, and other sensitive electronics without worry. The pure sine wave inverter and power factor corrected charger provide clean, reliable inverter power with low total harmonic distortion (THD) of less than 5%