Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number 54-905-251 found under Caliper Micrometer Weight by Fred V Fowler Company Inc. The National Stock Number assigned to this part is 5210012697610, and the Federal Supply Class is 5210 Measuring Tools Craftsmens. Our website is owned and operated by ASAP Semiconductor, a leading distributor of aviation and aerospace part numbers like 54-905-251.