Thank you for selecting Aerospace Aviation 360 for AT4021BB by Nkk Switches Of America Inc under Electromechanical Switches. We are proud to be an ASAP Semiconductor owned and operated website, a leading distributor of aviation and aerospace part numbers like AT4021BB. To help us better understand your parts requirements, please fill out an RFQ form for part number AT4021BB with your details, and our customer executive will respond to your RFQ in 15 minutes or less.