NUT

The MS21921-4J is a genuine Textron Aviation nut — a fastening or retaining hardware item used in the airframe. It is fitted to the Citation Excel, XLS, XLS+, XLS Gen 2. It carries an export classification of ECCN EAR99, weighs 0.03 pounds, and measures 0.65 (L) x 0.6 (W) x 0.65 (H) Inches. As an original-equipment (OEM) part supplied directly by Textron Aviation, the MS21921-4J is built to the aircraft maker's specification and cross-references the type design as documented in the maintenance data. Choosing the genuine part over an unapproved substitute preserves configuration control and simplifies inspection sign-offs. Because the Cessna Citation aircraft share extensive structure and hardware, a single part like this is often common across several variants. Strength grade and finish define aircraft hardware, so matching the specified part keeps the joint as designed. The factory part is built to the manufacturer's material and dimensional specification, so it installs as designed without the surprises a generic equivalent can bring. Choosing the genuine article over an unapproved part keeps mechanics' sign-offs clean and the aircraft's configuration exactly as certificated. The Cessna name is among the most recognized in aviation — founded in Wichita, Kansas in 1927 and part of Textron since 1992, today a cornerstone of Textron Aviation. Cessna's Citation line, launched with the Model 500 in the early 1970s, grew into the best-selling business-jet family in the world, spanning today from the light M2 to the super-midsize Longitude. To check availability, request a quote for MS21921-4J or browse more Cessna Citation parts on Flying411.