These P10 brackets and mounts can be used to build a portable sign or as brackets for any P10 build. They are designed to use M3x8 socket head screws to attach to the P10 holes. There is a mount included that will support a Beaglebone Black which is used to run the panels. The battery mount is designed to hold a 16750mAh USB battery pack from RAVPower. The battery dimensions should be close to 5.00 x 0.79 x 3.15 inches.
I designed these brackets and mounts using OnShape.