3M™ Glass Bubbles S32LD are engineered hollow microspheres made of soda-lime borosilicate glass with a Yes density of 0.29 g/cm³ and isostatic crush strength of 1500 psi / 103 bar.
They are used to reduce density without compromising strength for buoyancy modules and insulation systems in the oil and gas industry and in other applications as construction, electronics, and marine.