This helmet hasteners does not fit for 3M Adflo, Speedglas 9100fx, Miller Infinity series, Lincoln K2800-1. Female Cover head inside designed with a circular groove, come with one Silicone Washer(flexible&durable), perfect match male screw and your helmet, stay tight and never worry about flying-out. Body & knob made from light weight 6061-t6 aluminum. Item surface was anodized to create an glossy film which won't grow dark during long-time using. Knurled surface design, easy to twist in, and not easy to slide. Our fasteners fit for flip hood and replace easily damaged plastic fasteners. Fit for Fibre Metal 2090 with 3C headgear too. Please note that 3mirrors Brand products are Original Design, Designed to provide the best for welders. Any questions, please contact us for help., Manufacturer: 3mirrors