66" wide x 16" high horizontal compartment door with prime paint finish for Knapheide service bodies. Knapheide doors are known for their robust construction and often feature a thickness of 4 inches. This thickness is designed to provide durability and security for the storage and access of equipment and materials. Knapheide doors are known for their robust construction and often feature a thickness of 4 inches. This thickness is designed to provide durability and security for the storage and access of equipment and materials.