Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number GRXF20MMX1-4IN found under Disk Filter by Selas Corp Of America. The National Stock Number assigned to this part is 6605000899467, and the Federal Supply Class is . Our website is owned and operated by ASAP Semiconductor, a leading distributor of aviation and aerospace part numbers like GRXF20MMX1-4IN.