Such structural damage is often visually evident by the existence of white lines or patches in the laminate or around the point of impact. Damage which results in complete penetration should be repaired by an authorized fiberglass repair facility. Order touch-up paint or gel-coat separately (please call for colors available). Note: Before you begin your fiberglass repair you will need to purchase catalyst (methyl ethyl ketone peroxide) from an auto parts store, marina, or hardware store. Catalyst is a clear liquid hardener for gel coat that cannot be shipped because of mailing regulations. You only need a very small amount; 1 oz. easily does a quart of resin.