Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number 63950 found under Chalk Line And Reel by Irwin Industrial Tool Company. The National Stock Number assigned to this part is 5210014311867, and the Federal Supply Class is 5210 Measuring Tools Craftsmens. Our website is owned and operated by ASAP Semiconductor, a leading distributor of aviation and aerospace part numbers like 63950.