Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number MR-03-100 ITEM 52 found under Spring Helical Compression by Rulyn Inc. The National Stock Number assigned to this part is 5360012523580, and the Federal Supply Class is 5360 Coil Flat Leaf And Wire Springs. Our website is owned and operated by ASAP Semiconductor, a leading distributor of aviation and aerospace part numbers like MR-03-100 ITEM 52.