The Standard 10 Frame Lid is moulded to Langstroth standard dimensions, has migratory vents, the allocation for spring clips, and is interchangeable with your existing supers. The ribbed design gives the lid added strength, durability and is UV stable for 30+ years. Bases are easily stacked on top of lids for transport or storage purposes. The reinforced ribbing on the side of the lid gives added strength for strapping hives down tight. The rebated lid sits proud of the top box, comes down the outer sidewall locating over the top, eliminating any chance of rain entering the top box.