The ridges or flues on this USA Pan Cake Pan 9 x 13" help improve air flow during baking. You can count on this bakeware from USA Pan to properly bake your favorite treats. The structure and commercial grade aluminized steel in USA Pans distributes heat quickly and evenly. This bakeware is also highly durable and resists warping and denting. You won't hear that dreaded ping when you put these USA made pans in the oven! Removing baked goods from professional quality USA pans is a snap because of their silicone finish. This non-stick surface also makes for easy clean up! Best of all, USA pans really are made in the USA, in Pennsylvania, from 65% recycled steel.