Part Number 6321421-4 Doubler Skin Cntr Wg Lwr Aft in stock with ready to ship. Get an instant quote for Cessna Citation part number 6321421-4 by filling form below with your desired order quantity, targeted price and the expected order-fulfilment date. Get instant quote for 6321421-4. Our dedicated account manager will get back to you within 15 minutes.