Regular Lizard Skin is thicker than SD--Bob calls it "marshmallow cream consistency." The Nova got a coat of SD on the inside, followed by three coats of regular Lizard Skin. The underside was treated to four coats of regular Lizard Skin. Bob says it never hurts to go thicker (around .080-inch, or about the thickness of two credit cards) on hotter spots (near the exhaust, etc.).