This combo pak includes tank liner & tank prep. One easy part for all your repair needs. Sold as a kit. Tank Prep is a two-part kit that dissolves rust, etches the metal and removes oil and grease. Treatment time is approximately four hours. In a new or old tank, Kreem fuel tank liner will seal and protect, prevent rust and stop leaks from pinholes and hairline cracks. Resistant to alcohol and gasohol, withstands most octane boosters. Kit includes 1 pint Prep A, 1/2 pint Prep B, (enough for a 2-1/2 gallon tank) and one pint of Kreem fuel tank liner. Most tanks require one pint of fuel tank liner per three gallon capacity.