Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number 57K3503 found under Parts Kit Hose Asse by Eaton Aeroquip Inc. The National Stock Number assigned to this part is 4720014715063, and the Federal Supply Class is 4720 Hose And Flexible Tubing. Our website is owned and operated by ASAP Semiconductor, a leading distributor of aviation and aerospace part numbers like 57K3503.