410 Microlight™ is the ideal low-density filler for creating a light, easily-worked epoxy fairing compound especially suited for fairing large areas. Microlight mixes with epoxy with greater ease than 407 Low-Density filler or microballoons and is approximately 30% easier to sand after the epoxy/410 mixture cures. Epoxy thickened with Microlight feathers to a fine edge and is also more economical for large fairing jobs. Not recommended under dark paint or other surfaces subject to high temperatures.
VIDEO: Adding Fillers to Epoxy.