Tamco 5300 series primers boast a true direct to metal resin (same as in our clears) which means it can be used on the entire vehicle. Many others claim to be direct to metal but tell you not to apply on anything larger than the size of a quarter. Another unique attribute of this series is that has a really high build much like a polyester filler primer. However, while our build is the same, it has flexibility and won’t crack like a polyester. It also uses an actual ISO hardener that allows it to cross-link to the substrate.