TruFast Plasti-Grip CBW Flat Insulation Washers are the ultimate fastening solution for securing rigid insulation and building wrap to a variety of substrates, including masonry, foundation walls, wood, and steel. Featuring a 1-¾ in. Dia flat plastic washer, they deliver superior holding power while minimizing insulation facer damage with a flexible perimeter design. Designed for energy efficiency and labor savings, these washers reduce thermal bridging and air infiltration, making them an ideal choice for foundation walls, basements, garages, crawl spaces, attics, and both interior and exterior walls and ceilings.Compatible with screws, nails, and Tapcons, we recommend using SPAX #8 or #10 construction screws with a minimum ¼ in. Dia head for optimal performance. Shoot it, screw it, or nail it-PLASTI-GRIP Flat Insulation Washers provide a high-performance fastening solution for residential, commercial, and industrial applications.Key Benefits: Fast, Secure Installation - No pre-assembly required, reducing labor time. Superior Holding Power - 1-¾ in. tapered flat washer ensures a firm grip. Flexible Perimeter - Minimizes tearing of insulation facer. Energy Efficient - Reduces thermal bridging and air infiltration. Versatile Compatibility - Works with nails, screws, and Tapcons. Multi-Substrate Use - Ideal for wood, steel, masonry, and foundation walls. Use with - Rigid foam insulation, mineral wool, building wrap, and other energy efficient options.