TyreBeads Motorcycle Tire Balancing Beads 3 oz Kit + FREE Valve Core Tool + FREE Applicator Kit Includes 1 oz for front tire, 2 oz for back tire, valve core tool, and an applicator bottle and tube These are premium internal tire ceramic balancing beads. They work with tube type tires. Reusable, super hard, durable, and eco-friendly - will not rust, clump, or melt THESE ARE NOT GLASS, which is a softer material that has a tendency to break down into powder, which will clump and is a health hazard.