Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number 4S7-4-1788 found under Spacer Special by Hi Shear Corporation. The National Stock Number assigned to this part is 5342006865935, and the Federal Supply Class is . Our website is owned and operated by ASAP Semiconductor, a leading distributor of aviation and aerospace part numbers like 4S7-4-1788.