Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number 523-0755-001 found under Crystal Unit Set Qu by Rockwell Collins Inc. The National Stock Number assigned to this part is 5955007400786, and the Federal Supply Class is 5955 Oscillators And Piezoelectric Crystals. Our website is owned and operated by ASAP Semiconductor, a leading distributor of aviation and aerospace part numbers like 523-0755-001.