It is possible to use a V44 instead of the standard V15 in one of our 4 Watt (the Amp, Fuse 4W) or 6 Watt (Fuse 6W, 6 Watt Kit, Switch, OffGrid) . The V44 will offer about 3x more power storage, an additional 5V and faster charging for tablets and phones that charge best from 2A.
If you already have a product with a V15, get the V44
and the F3511-5521
If you haven't purchased yet, you can select the V44 upgrade under the accessories section on the product page.