Product Description The finishing washer has an increased bearing surface and the sunken design gives a clean appearance. The washer is designed for use with flat or oval head screws. The called out size is the inner diameter of the washer. From the Manufacturer The finishing washer has an increased bearing surface and the sunken design gives a clean appearance. The washer is designed for use with flat or oval head screws. The called out size is the inner diameter of the washer.