Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number ASTM B32 found under Flux Soldering by American Society For Testing And. The National Stock Number assigned to this part is 3439000695815, 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 ASTM B32.