Three metal circular D38999 assemblies are shown, with the XACT logo and "Engineered Manufacturing Solutions" text in the background, highlighting expertise in sealed and booted assemblies.

D38999-Based Assemblies: Built, Booted, and Sealed by XACT EMS

Reliable Componentry. Custom Assembly.

The MIL-DTL-38999 specification—originally developed in the 1970s—continues to define modern interconnects used in defense, aerospace, and industrial systems. These connectors, originating from industry efforts including those of the Bendix Scintilla Division (now part of Amphenol), established a foundation for rugged, high-density, environmentally sealed interfaces.

Today, MIL-SPEC connectors span a wide range of use cases—from missile systems and aircraft avionics to underwater robotics and autonomous vehicles. The connector families themselves are standardized, but the way they’re integrated into a system varies by application—and that’s where XACT EMS steps in.

XACT: From Connector to Complete Assembly

At XACT EMS, we don’t just stock connectors—we engineer complete interconnect solutions. Whether you’re dealing with vibration zones, temperature extremes, EMI/RFI exposure, or fluid ingress, we provide:

  • Overmolded harnesses for abrasion resistance and strain relief
  • Booted assemblies for sealed transitions and rugged environments
  • Complete cable and wire harnesses tailored to spec
  • Custom backshells, labeling, and potting for full turnkey integration

We work with the full range of MIL-SPEC connector styles to build harnesses that meet exact design, environmental, and electrical needs—from the front panel to the power source.

MIL-SPEC Connector Categories & Types

Here’s a categorized reference list of the major connector series and derivative types commonly integrated into our harness assemblies:

Classic MIL-SPEC Series

  • MIL-DTL-38999 Series I (LJT), II (JT), III (TV)
  • MIL-DTL-26482 Series II
  • MIL-DTL-83723
  • MIL-DTL-5015
  • MIL-DTL-22992 Class L

High-Temperature & High-Power Variants

  • High Temperature Series Five (engine and firewall-rated)
  • High Power 38999 (RADSOK®, Temper-Grip, >500A capable)
  • High Voltage 38999 (next-gen power interfaces)

Extreme Environment / Derivative Series

  • Deep Space 38999 (cryogenic)
  • HD38999 High Density (+30% contact density)
  • Dualok (high-vibration applications)
  • Aquacon (fluid immersion, subsea)
  • ETV38999 (cost-sensitive applications)

Printed Circuit Board (PCB) Mount

  • D38999 Series I/II/III with PC Tail Contacts
  • D38999 PCB Hermetics (sealed and shielded)

High-Speed Data & Fiber Optics

  • Quadrax, Twinax, Coax, USB 3.0, HDMI, GbE
  • Fiber Optic using MIL-PRF-29504, ARINC 801, JSFC, MT

EMI/EMP Filtered Connectors

  • D38999 Series I, II, III with filtering
  • TVS diode and MOV versions for transient suppression

Hermetic / Sealed Connectors

  • Glass-to-metal and epoxy seals across D38999 Series I/II/III
  • AmpheSEAL High Pressure sealing

Quick Disconnect / Breakaway

  • Breakaway Series (MIL-STD-1760-qualified)
  • T-Line Push-Pull
  • LJT Breakaway

Miniature & Micro-Miniature Series

  • 2M Micro 38999
  • Bantam Micro-Bayonet
  • Warrior Grip (wearable soldier systems)
  • MRC Multi-Media Ruggedized

Specialized Connector Options

  • Bulkhead Feedthroughs
  • Connector Savers
  • RoHS-Compliant Platings (AP-93, electroless nickel, etc.)
  • Jam Nut Styles (space-saving mount)
  • Integral Backshells, Dummy Receptacles, Caps

Built. Sealed. Delivered.

We specialize in transforming these standardized components into ruggedized interconnect harnesses, ready for field deployment. Whether you’re prototyping a small UAV interface or building out full vehicle architecture, our team helps configure, mold, and boot your assemblies to perform in the real world—not just on paper.

Let us know your specs—we’ll take it from there.

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