Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number 690-27 found under Valve Trim Rod by Bureau Of Mines Helium Operations. The National Stock Number assigned to this part is 6110009697041, and the Federal Supply Class is 6110 Electrical Control Equipment. Our website is owned and operated by ASAP Semiconductor, a leading distributor of aviation and aerospace part numbers like 690-27.