Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number CS 4921 found under Transformer Radio F by Coil Specialty Co Inc. The National Stock Number assigned to this part is 5950011626104, and the Federal Supply Class is 5950 Coils And Transformers. Our website is owned and operated by ASAP Semiconductor, a leading distributor of aviation and aerospace part numbers like CS 4921.