Print your own 90 degree and 45 degree adapter, for the popular Bosch GEX18V-125 random orbital palm sander.
 
Sanding the edge of a board or panel can be tricky, especially if you're trying to avoid introducing any bevel, and keep it at right angles to the adjoining face.  This adapter allows the sander to be kept at a 90-degree angle to the edge of your work piece.
 
If you're cutting bevels, especially 45 degree ones, you can swap out the 90 degree for a 45 one quickly and simply.

Included is the .STL file that you can import into your preferred slicer program to print your own adapters!

You'll require some additional hardware to mount your adapter to your sander:
 
2 x 20mm, M3 bolt (preferably button head)
1 x 30-40mm, M8 bolt
1 x M8 nut
2 x M5 nuts
2 x M5 Bolt, or finger knob (recommend)
 
Most filaments will be fine, mine are printed with standard PLA, %15 infill.