Hollow glass microspheres—lightweight, spherical particles with a smooth, reflective surface—are mainly made of alkali-lime borosilicate glass. They integrate unique properties: low density, high strength, low thermal conductivity, top-tier electrical insulation, temperature resistance, chemical stability, and excellent fluidity. These versatile microspheres find wide application in adhesives, corrosion-resistant & insulating coatings, construction materials, rubber, synthetic wood, oilfield cements, and lightweight automotive composites.