What are the different keyway polarizations of D38999 connectors?
What are the different sizes of D38999 connectors?
Learn how to assamble D38999 connectors.
Learn about the different shell sizes, styles and finishes.
Review D38999 insert arrangements.
Learn how to decode D38999 Part Number.
Part Number Breakdown

D38999 Part Number Breakdown.

Part Number Breakdown

D38999 assembly instruction.

Part Number Breakdown

List of MIL_DTL-D38999 part numbers.


Previously known as MIL-C-38999, MIL-DTL-38999 connectors come in four series: Series I, Series II, Series III and Series IV. They are environmentally resistant connectors that use removable crimp contacts and have an operating range of -65 to +200°C.

Series I connectors are bayonet coupled and have high-vibration properties. They are scoop proof and are ideal for heavy wind and moisture environments. They are utilised when a fast disconnect coupling system is required.

Series II connectors are bayonet coupled, are non-scoop proof, and have a low profile, so are used when weight or space is limited, or in low-vibration, high moisture, and strong wind situations.

Series III connectors are coupled by a quick screw Tri start thread, are scoop proof, and are best suited for normal mating and unmating applications and can be used in high temperature, moisture, wind, or vibration environments when used with the correct accessories. Series III connectors are most commonly use in Military and Aerospace designs.

Series IV connectors are coupled by a Breech-Lok mechanism, are scoop proof, lightweight and suitable for blind mating applications, and they also have high-vibration attributes. They are well suited in high wind and moisture environments when used with the appropriate accessories.

38999 Coupling Scoop Proof Durability High Impact Schock Bend Moment Price
Series I Standard Bayonet Yes 500 Yes 650 lbs in $
Series II Low-Profile Bayonet No 250 No 150 lbs in $
Series III Triple Start Threded Yes 500 Yes 1000 lbs in $$
Series IV Breach-Lok Yes 500 Yes – Heavy 1000 lbs in $$$

MIL-DTL-38999 Specifications and Datasheets

The most recent MIL-DTL-38999 specification can be downloaded from Defense Logistics Agency Land and Maritime website: click here to download.

Major manufactures of D38999 connectors include Amphenol, TE Connectivity, Glenair, Souriau, Conesys, ITT Cannon and Eaton. You can download each manufacturer’s datasheets using links in the following table.

Manufacturer Datasheet
Series I Series II Series III Series IV
TE Deutsch

Part Number Breakdown

D38999 Part Number Decoder Tool

Try our Part Number Decoder Tool! Enter any D38999 part number in the box below and we will decode it for you. We already entered the “D38999/” prefix so you don’t have to.


D38999 connector part numbers are composed of six sections in addition to the D38999 prefix:

Shell Type                      Material and Finish     Shell Size

Insert Arrangement     Contact Type                Keying Position


The meaning of the codes in each section is explained below.

Contact Us

We're not around right now. But you can send us an email and we'll get back to you, asap.

Not readable? Change text. captcha txt

Start typing and press Enter to search