Tuff-Boy Silicone Alkyd Enamels are premium gloss enamels that have been uniquely formulated with a silicone resin so that they are easy to apply, have good flow and leveling properties and outstanding gloss and color retention. The primary benefit of these products over a traditional alkyd enamel is the excellent gloss and color retention, which will provide for many more years of service. These weather resistant enamels also feature excellent hiding and outstanding durability, and have a much higher concentration of silicone resin than traditional silicone alkyds (greater than 30%). When used with the Tuff-Boy Rust Stop primers, these products provide excellent corrosion protection for ferrous metals. The performance level of these products, meet Federal Specification #TT-E-1593. All interior alkyd-based products may yellow in white and pastel colors that do not receive ultraviolet light. These products are also sold with a non-yellowing additive to improve the non-yellowing performance. Yellowing is an inherent characteristic of all alkyd resins. To avoid yellowing entirely from occurring, a water-based product is recommended.