38999-type circular connectors · Updated 2026-09-28
How to Read a 38999 Part Number
A 38999 part number tells you almost everything needed to order the connector. Our J599 Series III part numbers follow the same structure as D38999 part numbers, so the example below reads the same way for both.
Example: J599/20WB35SN
| Segment | Meaning in the example |
|---|---|
| J599/ | Series III-type connector |
| 20 | Connector type — square-flange receptacle |
| W | Finish — aluminum, olive-drab cadmium |
| B | Shell size code — B = size 11 |
| 35 | Insert arrangement — layout 35 in shell 11 (11-35: 13 × size 22D) |
| S | Contact type — socket |
| N | Key position — normal |
Connector type
| Code | Type |
|---|---|
| 20 | Square-flange (wall-mount) receptacle |
| 24 | Jam-nut receptacle |
| 26 | Plug |
| 21, 23, 25, 27 | Hermetic receptacles (square flange, jam nut, solder mount, weld mount) |
Shell size codes
Series III uses letters for shell sizes: A = 9, B = 11, C = 13, D = 15, E = 17, F = 19, G = 21, H = 23, J = 25. The number after the letter is the layout within that shell.
Finish letters
The finish letter sets shell material, plating, shielding, temperature class and salt-spray resistance. Common choices are nickel on aluminum (general use), olive-drab cadmium (high corrosion resistance, not RoHS compliant), nickel-PTFE, passivated stainless steel, composite and titanium. The J599 Series III page lists every finish with its test values.
Contact type
P = pin, S = socket. Hermetic receptacles use solder-sealed pins; feed-through receptacles use a separate code.
Key position
N is the normal key position; A, B, C, D, E rotate the keyways so that several identical connectors on one panel cannot be cross-mated. Use a different key for each connector of the same size and layout.
Suffixes
Some part numbers end with extra letters for special versions — for example fluorosilicone seals for fuel and oil exposure, or thermocouple contacts. When in doubt, send us the full part number and we will decode it and propose the matching configuration.
