3M™ Glass Bubbles K42HS are hollow glass spheres with a typical density of 0.42 g/cc and an isostatic crush strength of 7,500 psi. 3M™ Glass Bubbles are low density additives made from temperature stable glass. These hollow glass microspheres can be used as a low-density functional filler that is ideal for plastic and rubber parts created from injection molding, extrusion processes and/or other vigorous processing equipment. The unique spherical shape of 3M glass bubbles offers a number of important benefits, including: weight savings, dimensional stability improvement, cycle time reductions and process savings. These low-density spheres are used in a wide range of industries including automotive, construction materials, electronics, sports & leisure and marine.