Here is a vintage Pyrex de Corning casserole lid, no base. It is made of original borosilicate formula glass. When covered, this unique design forms a vented cooking vessel. One handle is marked Pyrex de Corning, another is marked 454 France N. The dish is 9 7/8" wide across the handles. The casserole was produced in the 1950s, it is a midcentury piece of kitchenware. It is in very condition with one minor chips on the rim near a handle.