MS21900-4
Military Standard Boss Nipple
outside diameter: 1/4", adapter, flareless tube to flared tube, carbon steel

MS21900-4 Datasheet Features and Specification
Quick Specs
Thread Series | UNJF |
Thread Class | 3A |
Material | Steel |
Additional Information
SKU / Model: | MS219004 |
NSN: | 4730-00-541-1579 |
FSC: | Hose, Pipe, Tube, Lubrication, and Railing Fittings / 4730 |
Product Series: | MS21900 |
Pack Weight (Approx.) | 0.058 lb |
Minimum Qty (MOQ): | 1 |
ECCN: | EAR99 |
National Motor Freight: | 052190, Pipe,tubing,or Pipe Or Tubing Fitti |
Download PDF Version MS21900-4_Military-Fasteners-com.pdf |
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Frequently bought together
Other customers frequently bought these along with MS21900-4

MS21900-5
Boss Nipple
in Fittings
outside 5/16", adapter, flareless tube to flared tube, carbon steel
MS21900-8
Boss Nipple
in Fittings
Outside diameter: 1/2", carbon steel, adapter flareless tube to flared tube, MS21900 series fitting
More MS21900 boss nipples
$41.94 Each, Aluminium alloy 7075 tube outside 1/2in. adapter flareless tube to flared tube
Aluminum alloy 7075, tube outside 5/16in., adapter flareless tube to flared tube
Aluminum alloy 7075, tube outside 1/4in., adapter flareless tube to flared tube
Aluminum alloy 7075, tube outside 5/8in., adapter flareless tube to flared tube
4730-00-080-3731 Boss Nipple
Corrosion resistant steel 304 tube outside 1/4in. adapter flareless tube to flared tube
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Customer Reviews

Another good experience with Military Fasteners, and our Sales Rep, Dan Hunter. We needed hardware for an older aircraft model, and Dan's expertise was exceptional. He quickly identified fasteners, even for parts with unclear descriptions, and provided invaluable technical assistance. The supporting data was spot-on, verified by our technicians. Despite finding slightly lower prices elsewhere, the unmatched service and expertise from Military Fasteners, particularly Dan, make them our preferred choice. Our order was delivered ahead of schedule. Highly recommend MilFast for top-notch service and technical support!
Milfas is a great company to work with. They have good prices and great customer service! Ashili and Lindsey are great to work with.
Ordered on a Monday evening and arrived in New Zealand Friday afternoon. Very good prompt service and the compass was installed on the Saturday after calibration. Thanks Military Fasteners!
I could find those 2 great different products for my Garmin at the same place. Thank you very much, very helpful, very easy to order and fast shipping.
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