Stress Plates are designed for use with Deck Screws and Spike anchors. For Powerlite specially designed stress plates are listed in the applicable product sections. Stress plates are used when attaching insulation and single ply materials to distribute load and prevent the material being fastened from pulling over the head of the fastener. In addition to the stress plates, a sealing washer and a plastic bearing washer are available for use with flashing and termination systems.