Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number M158-4261 found under Flange Pipe Blind by Heil Trailer International Co. The National Stock Number assigned to this part is 4730015048927, 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 M158-4261.