Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number 21338508 found under Crystal Unit Quartz by Henley Marine Inc. The National Stock Number assigned to this part is 5955010076619, 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 21338508.