The 3 Pack of Irontite Additives - Thoro-Flush, All Weather Seal and Ceramic Motor Seal. 468-9190-16 All 3 Irontite Cooling System Additives in One Box for the Ultimate Fix Step 1: ThoroFlush - Loosens and Removes Rust, Scale, Grease, Oil and Sludge to Improve Coolant Flow Step 2: Ceramic Seal - Coats to Fill Cracks and Porousness. Prevents Rust, Corrosion and Leaks Step 3: All Weather Seal - Permanently Blends with Coolant to Stop Leaks When and Where They Occur The Most Effective and Longest Lasting Leak Protection You Can Buy!