Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number 2550000056 found under Ring Wiper by Hydro Line Mfg Co. The National Stock Number assigned to this part is 2590012222742, and the Federal Supply Class is 2590 Miscellaneous Vehicular Components. Our website is owned and operated by ASAP Semiconductor, a leading distributor of aviation and aerospace part numbers like 2550000056.