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38999 S III
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MIL-DTL-38999
Features and Application
Series III
Features and Application
MIL-DTL-38999 Series III is the newest cylindrical connector
designed for highest performance capabilities used in both
general purpose and severe environment applications.
ese connectors feature an improved “one-turn” coupling
system, utilizing self-locking acme thread. Acme threads
provide coupling durability, while thicker wall sections and
greater coupling surface area improve strength and shock
resistance. Blunting of the threads on both receptacle and
plug coupling nut eliminates cross threading.
Elongated mounting holes permit the Series III Connector to
intermount with various existing Mil-spec ange mounted
receptacles, giving it a design replacement advantage.
Wall mount receptacle, jam nut receptacle and straight
self-locking RFI plug are oered in 9 shell sizes and 54 insert
arrangements utilizing M39029 contacts in sizes 22D, 20, 16,
12, 10 power and 8 twinax.
ese connectors are available in wide range of shell materials
and nishes. Aluminum shells are oered in electroless nickel
and olive drab cadmium. Other nishes such as anodic and
zinc cobalt are available upon request to commercial callouts
only. In addition, we oer stainless steel shells (both passivated
and electro-deposited nickel plated) with rewall inserts, and
for highly corrosive environments, nickel-aluminum-bronze
shells with standard environment-resisting inserts (commer-
cial callouts only).
MIL-STD-1560 Insert Arrangements – Series III connectors
use insert patterns and contacts common to Series I,
making for an easy transition from bayonet to triple-lead,
acme-thread, self-locking coupling.
Metal-to-Metal Bottoming – is feature precludes relative
shell-to-shell motion, which may result in ordinary connector
wear and moisture entrapment.
Lockwiring Eliminated – Self-locking quick coupling plug
eliminates the need for lockwiring.
Firewall Capability - Stainless steel shells in both K and S
rewall classes are oered.
Universal I/R Tool – A single, expendable plastic tool is used
for both insertion and removal of contacts.
Scoop-Proof Design – Recessed pins in elongated shells
minimize the possibility for contact damage. In a blind
mating application, mating shells cannot “scoop” the pins,
and cause a shorting or bending of contacts.
Closed-Entry Socket Insert – Hard dielectric socket face
has lead-in chamfers for positive alignment of pins (even
partially bent within pre-established limits) with sockets.
Interfacial Pin Insert Seal – Raised moisture barriers
around each pin, which mate into lead-in chamfers of
hard face socket insert, provide individual contact sealing.
Interfacial seal is never touched by service tools.
Elastomer Wire Sealing Grommet – Sealing over a wide
range of wire diameters is assured by a triple wire seal in
each cavity at the rear of the connector.
Superior Contact Stability – Rear release crimp contact
system features a stamped beryllium-copper retaining clip
captivated by molded-in shoulders of each contact cavity in
the insulator. A rear-inserted M81969 plastic tool expands
the tines beyond the shoulder, releasing the contact.
Metric Accessory Thread – Metric thread results in
additional wall thickness giving greater strength and shock
resistance.
Twinax Contacts – Aero Electric is Qualied to make and
supply M39029/90-529 and M39029/91-530 size 8 Twinax
contacts used in 38999 III connectors. Please consult factory
even when needing to buy just the contacts.
