Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number 266-0123-020 found under Boot Dust And Moist by Rockwell Collins Inc. The National Stock Number assigned to this part is 5975012728510, and the Federal Supply Class is 5975 Electrical Hardware And Supplies. Our website is owned and operated by ASAP Semiconductor, a leading distributor of aviation and aerospace part numbers like 266-0123-020.