Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number 31-506 found under Sander Belt Combination Vertical by Rockwell International Corp. The National Stock Number assigned to this part is 3220002480892, and the Federal Supply Class is 3220 Woodworking Machines. Our website is owned and operated by ASAP Semiconductor, a leading distributor of aviation and aerospace part numbers like 31-506.