Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number EK602HB found under Filter Element Fluid by Watts Regulator Co. The National Stock Number assigned to this part is 4330007321793, and the Federal Supply Class is 4330 Centrifugals Separators And Pressure And Vacuum Filters. Our website is owned and operated by ASAP Semiconductor, a leading distributor of aviation and aerospace part numbers like EK602HB.