Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number 1540 found under Block Tackle by Harken Incorporated. The National Stock Number assigned to this part is 3940014585760, and the Federal Supply Class is 3940 Blocks Tackle Rigging And Slings. Our website is owned and operated by ASAP Semiconductor, a leading distributor of aviation and aerospace part numbers like 1540.