Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number NDC50419-0410-21 found under Levonorgestrel And by Bayer Healthcare Llc. The National Stock Number assigned to this part is 6505011853301, and the Federal Supply Class is . Our website is owned and operated by ASAP Semiconductor, a leading distributor of aviation and aerospace part numbers like NDC50419-0410-21.