The piggyback gives you more flexibility with a minimum of fuss and weight. It attaches to the lid using existing box hardware and a simple velcro strap, giving you the option of carrying larger panels.
The nice thing about the piggyback is that it frees you to paint square format, or the next common size up beyond the regular box capacity, without having to rig up a separate panel carrier (or buy another box!)
Sunclips attach to the lid or the piggyback. The piggyback can lift the sunclips up above the painting panel for larger or vertically placed panels.
In the photos above and right, the piggyback adapter for the Blackfoot is shown as an example.
For more details and a clear idea of how the Piggyback Adapters work, see the video demos.