Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number 12-20L-M-DC found under File Rotary by Johnson Carbide Products Inc. The National Stock Number assigned to this part is 3455010511390, and the Federal Supply Class is 3455 Cutting Tools For Machine Tools. Our website is owned and operated by ASAP Semiconductor, a leading distributor of aviation and aerospace part numbers like 12-20L-M-DC.