Please fill out the form below for Nut Plain Hexagon and get a quote for part number HEX NUT 4-40UNDERSIZE3 16 by M C L Inc with NSN 5310015077478 and FSC Name is 5310 Nuts and Washers, please include required quantity along with expected turn around time. Our knowledgeable account manager will reply you shortly. Also check for the related parts for part number HEX NUT 4-40UNDERSIZE3 16. ASAP Aerospace distributes nose to tail NSN components, sub-assemblies, and assemblies for the aerospace and aviation industry.