You are looking at a Vintage 2 1/2 Quart Corning Ware Casserole Dish.  Complete with glass lid.  Model # P- 2 1/2-B made in U.S.A. marked on the bottom.  This is the Cornflower designed dish.  No cracks or scratches that we can see.  We have several Corning Ware Dishes up for sale in the Blue Cornflower design.