Baker's Half Sheet and Quarter Sheet natural aluminum commercial bakeware is made of pure aluminum which will never rust for a lifetime of durability;Baked goods rise and bake evenly due to aluminum's superior heat conductivity and the reinforced encapsulated steel rim prevents warping;Pan dimensions, Half Sheet exterior 17.88 x 12.88 x 1.06, interior 16.5 x 11.38 x 1 inches, Quarter Sheet exterior 12.94 x 9.63 x 1.13 inches, interior 12.25 x 8.75 x 1 inches;Easy clean up, hand wash only;Proudly made in the USA by Nordic Ware