The HP Polymer Seam Plate is specifically designed for use with EPDM RUSS and the Sure-Tough™ EPDM membrane on Carlisle's mechanically fastened EPDM roofing systems over steel decks. It offers improved back-out resistance by creating a friction fit between the fastener and the plate recess. The 16 barb profile on the underside of the plate reduces lateral movement of the plate when subjected to dynamic membrane loading.