TRANSTAR® 4613 2 in 1 Primer, 20 oz Aerosol Can, Black, 15 to 20 min Dry Curing2 in 1 primers are a specialty coating designed for easy and convenient priming of metal and plastic parts. These primers help prevent rust and seal out moisture, while providing a smooth base for topcoat application on metal substrates. 2 in 1 primers also have excellent flexibility and adhesion properties that enable them to be applied to flexible and rigid parts. 2 in 1 primers are fast drying, provide superior fill and build, and are easy to sand.