Supertest porcelain sign features the iconic Maple Leaf with large Supertest lettering across the center. It measures 11 3/4 and has excellent porcelain. Whether you are displaying this sign as part of your collection in your man cave, shop, bar, or garage, or giving it as a gift, you can also browse my other auctions for more vintage gas, oil, comics, automobile, motorcycle, and hunting signs. Vintage Supertest porcelain sign. Bright colors w/ porcelain on both sides.