Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number B109TK found under Diaphragm by Foxboro Co. The National Stock Number assigned to this part is 4820008742337, and the Federal Supply Class is 4820 Valves Nonpowered. Our website is owned and operated by ASAP Semiconductor, a leading distributor of aviation and aerospace part numbers like B109TK.