Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number QQ-R-566 found under Rod Welding by Federal Specifications. The National Stock Number assigned to this part is 3439000635200, and the Federal Supply Class is 3439 Miscellaneous Welding Soldering And Brazing Supplies And Accessories. Our website is owned and operated by ASAP Semiconductor, a leading distributor of aviation and aerospace part numbers like QQ-R-566.