They are made from a woven-glass reinforced/ceramic-filled thermoset and have a >280°C glass transition temperature. And unlike PTFE-based microwave materials, no special throughhole treatments or handling procedures are required. This lets standard epoxy/glass (FR4) processes be used during part fabrication.
Rogers Corp. Box 188, One Technology Dr. Rogers, CT 06263 (860) 779-4045 rogercorporation.com