Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number NORTON MH 14 found under Lens Helmet Welders by Siebe North Inc. The National Stock Number assigned to this part is 4240005402420, and the Federal Supply Class is 4240 Safety And Rescue Equipment. Our website is owned and operated by ASAP Semiconductor, a leading distributor of aviation and aerospace part numbers like NORTON MH 14.