Add these Glass Microshperes to epoxy to create a lightweight fairing compound that’s easy to sand or shape. If sagging is a concern, Silica Thickener may be added. TotalBoat fillers can be used with either epoxy or polyester resins to change the resin properties for various uses, such as bulking out the resin or making it easy to sand. Because fillers can affect the pot life of a resin, create a small trial batch first to determine how much working time you’ll have.Glass Microballoons DetailsLightweight glass balloons or bubbles that are easy to sand when cured. Perfect for smooth finish work.Provides good impact strength.Can be used alone or blended with TotalBoat Silica Thickener (sold separately) to prevent sagging on vertical and overhead surfaces.Color: WhiteSize: Available in 1-Quart and 5-Quart sizesAlways wear proper safety protection when blending Glass Microballoons and other fillers into mixed resin/hardener, and when sanding.Not recommended for gluing.