Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number MS51531B8 found under Nut Tube Coupling by Parker Hannifin Ltd. The National Stock Number assigned to this part is 4730007621239, and the Federal Supply Class is 4730 Hose Pipe Tube Lubrication And Railing Fittings. Our website is owned and operated by ASAP Semiconductor, a leading distributor of aviation and aerospace part numbers like MS51531B8.