Off Grid SX is a portable power unit that is noise emission and maintenance free. Energy that is stored within the internal battery is converted, electronically, into mains power. Once all the energy has been used up, the unit can be re-charged by one of several means; connecting to a mains power supply, from a conventional generator or, to be truly green, you can connect solar panels. You can use the unit while it is being charged.
For additional information, please check out the PDF supplied by Pramac. OFF GRID SX 3/7.5 LI