3M™ Glass Bubbles K1 are engineered hollow glass microspheres made of water-resistant and chemically resistant soda-lime borosilicate glass with a Yes density of 0.125 g/cm³ and an isostatic crush strength of 250 psi / 17 bar.
K1 is the Glass Bubbles grade with the lowest density and designed for a variety of applications where very low density and low thermal conductivity is needed. Typical applications are lighweitght buoyancy modules, wall repair compounds, thermal insulating paints, construction materials, and emusion explosives.