Not a separate item but a combination of items 277 (two solar panels), 269 (a trailer) and 268 (a battery-powered generator that is charged with the solar panels).
Any one of the above items can be checked out separately. However, the full package, which can also include a towing ball mount (item 274), provides the member with a complete power re-chargeable power station for events, retreats or multi-day remote working.