Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number 523 6 found under Packing Leather Cup by Bureau Of Mines Helium Operations. The National Stock Number assigned to this part is 2815009633549, and the Federal Supply Class is 2815 Diesel Engines And Components. Our website is owned and operated by ASAP Semiconductor, a leading distributor of aviation and aerospace part numbers like 523 6.