3M™ Glass Bubbles iM16K are high-strength polymer additives made from a water-resistant and chemically-stable soda-lime borosilicate glass. These hollow glass microspheres can be used as a low density filler material ideal for plastic and rubber parts created from injection molding, extrusion processes, and/or other vigorous processing equipment (e.g., Banbury mixers, etc.), offering improved processing over many conventional fillers. They can reduce final part weight by 15% or more without compromising the mechanical integrity.