Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number CS4720-0021F03ZNR found under Tubing Nonmetallic by Crown Systems Co. The National Stock Number assigned to this part is 4720005294521, and the Federal Supply Class is 4720 Hose And Flexible Tubing. Our website is owned and operated by ASAP Semiconductor, a leading distributor of aviation and aerospace part numbers like CS4720-0021F03ZNR.