D38999/26FF35SN

D38999/26FF35SN — MIL-DTL-38999 Series III Straight Plug (Shell Size 19, 66 Socket Contacts, Nickel Finish)

D38999/26FF35SN is a MIL-DTL-38999 Series III circular connector — a free-hanging (in-line), self-locking straight plug with EMI/RFI grounding fingers, carrying 66 gold-plated crimp socket contacts in shell size 19, with an electroless nickel finish for a lightweight, non-magnetic alternative to cadmium-plated shells. It withstands extreme shock, vibration, and temperature extremes while mating via  rapid tri-start quick-coupling thread.

Key Specifications

How to Read the Part Number

D38999/26FF35SN breaks down as follows:

• D38999/26 — Base MIL-DTL-38999 Series III part number for a free-hanging, self-locking straight plug with EMI/RFI grounding fingers
• F (1st letter) — Shell finish: aluminum, electroless nickel (48-hour salt spray, -65°C to +200°C — a wider temperature range than cadmium-plated Class W, but lower corrosion resistance)
• F (2nd letter) — Shell size letter code for shell size 19
• 35 — Insert arrangement, defining a 66-position contact layout (contact count varies by shell size — the same “35” arrangement code yields different contact counts on different shell sizes)
• S — Contact type: socket (female) contacts
• N — Polarization/keying position: normal

Note that the finish code and shell size code both happen to be “F” in this part number — don’t confuse the two “F”s; they represent different attributes.

Typical Applications

• Military and commercial aerospace wiring harnesses requiring a lighter, non-magnetic shell
• High-temperature avionics and engine-area wiring (up to 200°C)
• Multi-signal data and control harnesses in radar, shipboard, and ground vehicle electronics
• Ground support and test equipment requiring a mid-to-high density MIL-qualified disconnect

Mating Information

D38999/26FF35SN is a free-hanging plug designed to mate with either D38999/20FF35PN (wall-mount receptacle) or D38999/24FF35PN (jam-nut mount receptacle) — both share the same shell size 19 and insert arrangement 35, fitted with pin contacts. Always confirm the exact mating part number and finish class against your harness drawing before ordering.

FAQ

1. What does D38999/26FF35SN mean?

It decodes to a MIL-DTL-38999 Series III straight plug (/26), electroless nickel finish (F), shell size 19 (F), insert arrangement 35 (66 positions), socket contacts (S), normal keying (N).

2. How many contacts does D38999/26FF35SN have?

66 socket contacts, per insert arrangement 19-35.

3. What is the shell size of D38999/26FF35SN?

Shell size 19 — shown by the second letter “F” in the part number (shell size letter codes: A=09, B=11, C=13, D=15, E=17, F=19, G=21, H=23, J=25).

4. What’s the difference between D38999/26FF35SN and D38999/26WF35SN?

They share the same shell size (19), insert arrangement (35, 66 positions), and contact type (socket). The only difference is the shell finish: FF35SN uses electroless nickel (F) — lighter, non-magnetic, rated to 200°C but only 48-hour salt spray — while WF35SN uses olive drab cadmium (W), rated to 175°C with 500-hour salt spray. Choose based on your environment and weight/temperature requirements.

5. What contacts and crimp tools does D38999/26FF35SN use?

It uses standard AS39029/M39029 crimp socket contacts, size #22D; contacts and the corresponding insertion/removal and crimp tooling are typically ordered separately.

6. Is there a receptacle version of this connector?

Yes — D38999/20FF35PN (wall mount) and D38999/24FF35PN (jam nut) are the matching receptacles, same shell size and insert arrangement, fitted with pin contacts.