This is AEGIS® Crack Filler Resin. It is a special low viscosity formula that is the perfect choice for star breaks, combination breaks and cracks. Each 4 mL bottle contains enough resin for up to approximately 25 repairs, and has an unopened shelf life of two years. Mylar squares are required for curing (HDW3000) and are sold separately. Make AEGIS Tools the provider for all your high quality windshield fixes.