Used to stabilize water-filled punching bags. Water based punching bags tend to 'walk' or 'drift' as you hit them. Adding stretch bands to the base absorbs much of the impact and prevents walking or severely reduces.

1). Get thick rubber mat (3/8" used)
2). Cut 5/8" Particle board (or MDF/Plywood) into square with same size as water base .
3). Screw rubber mat into wooden board. Use lots of screws since you want the rubber to absorb as much energy as possible. Also make sure to sink the screws into the rubber so they dont scratch the floor. Careful not to screw too far and into the water base as this will damage your punching bag base.
4). Screw in Baseplate.stl (from this project file) into board corners (7/8" dry wall screws)
5). Wrap GoZone High Resistance Rubberband (from Walmart) around post (as shown in figure). Two bands are needed for all 4 corners.
6). Clamp band to corner Baseplate.stl using FastenerPlate.stl and pre-drill and screw down with 1-1/8" drywall screws.

Enjoy a non-permanent punching bag installation that barely moves with workouts and no floor/ceiling/wall damage. (At the cost of added complexity).