Series IV uses the same basic part-number field order as Series III (see the Series III part-number guide). This example is from the current Series IV builder:
D38999 /44 W H 23 S A
The compact part number is D38999/44WH23SA. The spaces above are visual separators. This example identifies a /44 jam-nut receptacle, class W, shell size 23 (H), insert arrangement 23, socket contact style S, and alternate polarization A.
Read each field
| Field | Example | Meaning |
|---|---|---|
| Specification designator | D38999 | MIL-DTL-38999 connector part-number family. |
| Slash sheet / shell style | /44 | /44 identifies a jam-nut receptacle in the current builder. |
| Class | W | General-purpose class code for material and finish requirements. |
| Shell-size code | H | Series III/IV letter code; H means shell size 23. |
| Insert arrangement | 23 | Contact layout, selected from the arrangement data for the shell size. |
| Contact style | S | Socket, 500-cycle contact style in the general-purpose family. |
| Polarization | A | Alternate keying position A. Series IV writes a polarization letter explicitly, including normal N. |
Shell-style codes represented in the current builder
| Code | Shell style |
|---|---|
/40 | Wall-mount receptacle |
/42 | Box-mount receptacle |
/44 | Jam-nut receptacle |
/46 | Plug with EMI grounding fingers |
/47 | Straight plug |
/41 | Hermetic box-mount receptacle |
/43 | Hermetic jam-nut receptacle |
/45 | Hermetic solder-mount receptacle |
/48 | Hermetic weld-mount receptacle |
This is the current tool dataset. Its Series IV slash-sheet list has not yet been cross-verified against MIL-DTL-38999 Supplement 1. The builder flags this review status; verify the exact shell style and sheet against the current controlling document.
Class codes currently offered
| Class | Current dataset description |
|---|---|
C | Aluminum, anodic nonconductive finish |
F | Aluminum, electroless nickel conductive finish |
G | Aluminum, electroless nickel conductive finish, space grade |
K | Stainless steel, passivated conductive/firewall class |
T | Aluminum, nickel-fluorocarbon polymer conductive finish |
W | Aluminum, cadmium olive-drab conductive finish |
N | Hermetic stainless steel, electrodeposited nickel conductive finish |
Y | Hermetic stainless steel, passivated conductive finish |
The base specification's class table has additional designators; this builder provides a practical subset whose applicability requires further review before expanding it. The table above is not the complete specification class list.
Shell-size codes
Series IV's current data covers shell sizes 11 through 25. It does not include shell size 9 because the source figures and arrangement dataset used for this tool do not cover that size for Series IV.
| Code | Shell size | Code | Shell size | Code | Shell size |
|---|---|---|---|---|---|
B | 11 | C | 13 | D | 15 |
E | 17 | F | 19 | G | 21 |
H | 23 | J | 25 |
The shell-size field is a letter code, not the size number itself. For example, H represents shell size 23.
Contact-style codes
General-purpose contact styles represented in the current Series IV data:
| Code | Meaning |
|---|---|
P | Pin, 500-cycle |
S | Socket, 500-cycle |
H | Pin, 1,500-cycle contact |
J | Socket, 1,500-cycle contact |
R | Pin, rhodium-plated contact |
M | Socket, rhodium-plated contact |
G | Pin, heavy-gold-plated contact |
U | Socket, heavy-gold-plated contact |
Hermetic contact styles represented in the data are fixed pin terminations: P solder cup, X eyelet termination, and C feed-through. The tool does not include hermetic socket-side styles while their applicability remains unresolved in the builder's source review.
Polarization codes
The current Series IV data lists N (normal) and alternate positions A, B, C, D, K, L, M, and R. Unlike Series I and II, Series IV includes a letter for the normal position in the part number. The current tool does not render a Series IV keyway diagram, so verify the physical keying from the current drawing and applicable specification.
Insert arrangement and data scope
The insert-arrangement field identifies the contact layout; the builder uses MIL-STD-1560 arrangement data shared with Series III for the supported Series IV shell sizes. Available choices depend on shell size. The Series IV tool focuses on general-purpose and hermetic styles and excludes lanyard-release, filtered, and NATC variants from its current data scope.
Verify before use
The current builder data is based on MIL-DTL-38999N with Amendment 2 and MIL-STD-1560 arrangement data. Check its visible review flags, especially the shell-style source note, and verify the complete PIN, class, interface dimensions, polarization, contacts, and applicable detail sheet against the current specification before design release or procurement. This site does not currently provide live supplier price or lead-time data.