Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number R03A found under Crystal Unit Quartz by Cooper R Jr Inc. The National Stock Number assigned to this part is 5955009544456, 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 R03A.