Oros strike indicators enclose fastening hardware inside of two molded soft foam hemispheres. When closed, the foam hemispheres compress creating a pressure fit lock that keeps it on the line and in place, without kinking. Over-sized threads make securing it to the line effortless. Recommended line weights by size: small - 5X and lower, medium – 4X or lower, large - 3X or lower Does not kink the line Float as much or more weight than the current leading brands. Smooth surface developed to repel water and dirt, and create less drag while casting Made with a Biodegradable additive that accelerates biodegradation with prolonged exposure in natural environments, not in normal use Strike indicator top and bottom colors can be mixed or matched by anglers for optimal visibility Available in 3 sizes and 3 colors.