Reliable Material: These washers are made of polypropylene, a plastic material, featuring good insulation, low profile, and good durability, which are easy to handle Size Information: The plastic washers are about 45 mm (1.77 inches) in diameter, and the center hole is about 5 mm Sufficient Quantity: You will receive 200 washers for screws and nails, suitable for daily use and replacement in foam board insulation and other applications Fixing and Supporting: These plastic washers are designed for fixing and supporting expanded polystyrene sheets, extruded polystyrene, and various types of foam boards Easy to Install: The round washers are easy to attach with screws or nails and can be removed as needed; Extra washers can be stored for future use Color: White Material: Plastic Package Contents: 200 x Plastic Insulation Washers Note: Light reflection and different display settings may cause slight variations in color between the image and the actual item. Measurement may vary by +/- 1-3 cm