CAB-O-SIl is a polyurethane thickener additive. The Cabosil is a thickener for silicone and polyurethane rubbers and resins in powder form. The fiber particles attract the moist materials, making the material much more thixotroper. Cabosil is widely used in making layer-up / brush molds of rubber or polyurethane resin mold shels.
The Cabosil can easily be mixed with the rubber until the desired thickness is reached. The rubber or resin can then be applied simply with a brush or with a spatula.