3M Glass Bubbles, 1 lb. Bag
Hollow glass microspheres, use to extend resin, to reduce weight, shrinkage and sanding effort.
Commonly used to make lightweight fairing compounds or putty for ding repair, also known as Q-cil. Can also be used to make tooling paste or cast parts.
A basic putty recipe is:
1 part resin by volume to 1 part 3M bubbles by volume - add cabosil to get desired thickness
The 3M Bubbles will extend and thicken the resin to a degree, but it is a bunch of marbles in solution so it will want to run and level out, adding cabosil will allow you to make a paste that you can stick on a wall or ceiling (if so desired) and won't affect the ability to sand the cured putty.