Part Number FFB571TYPEA4 having (CAGE Code 81348) and FSC 5310 Nuts and Washers in stock with ready to ship. Get an instant quote for FFB571TYPEA4 Nut Plain Castellated Hexagon by Federal Specifications Promulgat. Fill the form below with your desired order quantity, targeted price and the expected order-fulfilment date. Our dedicated account manager will get back to you within 15 minutes.