Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number 4391-1L3 found under Filter Low Pass by Hubbell Harvey Inc. The National Stock Number assigned to this part is 5915012276283, and the Federal Supply Class is 5915 Filters And Networks. Our website is owned and operated by ASAP Semiconductor, a leading distributor of aviation and aerospace part numbers like 4391-1L3.