Are you in search of MS21921 / AS21921 or (Nut, Sleeve Coupling, Flareless)? Here at ASAP AOG, we stock and supply over 6 billion new, old, and obsolete aviation parts that have each been inspected and certified by the FAA as well as other aviation authorities. We’re confident in our abilities to procure MS Fitting parts that fit with MS21921 / AS21921 (Nut, Sleeve Coupling, Flareless). Whatever item you need, be it an aircraft hydraulic fittings part or an PMA engine item, ASAP AOG is your one stop shop. Contact us today and receive an immediate quote in as little as 5 minutes.