J1784 Backshells for 38999-Type Connectors
Straight and 90° · cable clamp 2.49–21.67 mm · 360° shield termination

38999 Series II type · low-profile bayonet · 96 insert arrangements
GJB599 Series II is our 38999 Series II-type connector: a low-profile bayonet design with short, light shells for equipment where space and weight matter. It is built to GJB 599A Series II, with shell sizes 8 to 24 and 96 insert arrangements.
| Parameter | Value | Condition |
|---|---|---|
| Dielectric withstanding voltage, service rating M | 1300 Vrms / 800 Vrms | Sea level / 21,000 m altitude, mated |
| Dielectric withstanding voltage, service rating N | 1000 Vrms / 600 Vrms | Sea level / 21,000 m altitude, mated |
| Dielectric withstanding voltage, service rating I | 1800 Vrms / 1000 Vrms | Sea level / 21,000 m altitude, mated |
| Dielectric withstanding voltage, service rating II | 2300 Vrms / 1000 Vrms | Sea level / 21,000 m altitude, mated |
| Insulation resistance | ≥ 5000 MΩ | Room temperature |
| Insulation resistance | ≥ 1000 MΩ / ≥ 200 MΩ | High temperature, non-hermetic / hermetic |
| Insulation resistance | ≥ 100 MΩ | After humidity |
| EMI shielding | 45 dB at 1 GHz | Aluminum shells |
| Parameter | Value | Condition |
|---|---|---|
| Coupling | Bayonet | |
| Durability | 500 mating cycles | 250 cycles for JY27484 shielded plugs |
| Shock | 300 g, 3 ms |
| Parameter | Value | Condition |
|---|---|---|
| Operating temperature | −65 to +200 °C | −65 to +175 °C for cadmium finish |
| Random vibration | 100–1000 Hz, 1 g²/Hz (41.7 g rms) | |
| Damp heat, cyclic | 10 cycles × 24 h | GJB 1217A, type II |
| Hermetic receptacle leak rate | ≤ 1 × 10⁻⁸ Pa·m³/s | 0.1 MPa pressure differential |
| Operating altitude | ≤ 30,480 m | |
| Mould resistance | Grade 2, 28 days | GJB 150 |
GJB 599A Series II — Chinese specification for Series II low-profile bayonet connectors, the counterpart of MIL-DTL-38999 Series II.
Values not listed above — for example vibration level, leak rate or other environmental tests — can be tested to your requirements, including third-party testing. Specifications are subject to change; contact us for the current datasheet.
| Series code | Version | Notes |
|---|---|---|
| JY27473T | Plug | |
| JY27484T | Shielded plug | |
| JY27472T / JY27497T | Wall-mount square-flange receptacle, front / rear mounting | |
| JY27513E / JY27508E | Box-mount square-flange receptacle, front / rear mounting | |
| JY27474T | Jam-nut receptacle | |
| JY27902T | Round-flange adapter receptacle | |
| JY27476Y / 27477Y / 27478Y | Hermetic receptacles: wall mount / jam nut / solder mount | |
| JY27472Y …C | Hermetic bulkhead feed-through receptacle | |
| JY27…M | Marine-environment version (M) | Aluminum olive-drab cadmium (B), stainless (E) or titanium (TA) shells, 500 h salt spray; rated for acid salt spray, acid atmosphere and mould. Example: JY27472T14ME35PN. |
| Code | Shell material | Finish | Shell conductivity | EMI shielding | Temperature | Salt spray |
|---|---|---|---|---|---|---|
| F | Aluminum alloy | Electroless nickel | 1 mΩ | 45 dB at 1 GHz | −65 to +200 °C | 48 h |
| B | Aluminum alloy | Olive-drab cadmium | 2.5 mΩ | 45 dB at 1 GHz | −65 to +175 °C | 500 h |
| E | Stainless steel | Passivated | 50 mΩ | — | −65 to +200 °C | 500 h |
| TA | Titanium alloy | None (bare titanium) | 10 mΩ | 65 dB at 10 GHz | −65 to +200 °C | 500 h (marine version) |
| Contact size | Engaging diameter | Contact resistance | Contact resistance (hermetic) | Current rating | Wire size |
|---|---|---|---|---|---|
| 22D | 0.76 mm | ≤ 14.6 mΩ | ≤ 28 mΩ | 5 A | AWG 22–26 (0.13–0.33 mm²) |
| 22 | 0.76 mm | Tested to your requirements | — | 5 A | AWG 22–26 |
| 20 | 1.02 mm | ≤ 7.3 mΩ | ≤ 12.0 mΩ | 7.5 A | AWG 20–24 (0.20–0.52 mm²) |
| 16 | 1.58 mm | ≤ 3.7 mΩ | ≤ 8.5 mΩ | 13 A | AWG 16–20 (0.52–1.31 mm²) |
| 12 | 2.41 mm | ≤ 1.83 mΩ | ≤ 5 mΩ | 23 A | AWG 12–14 (2.08–3.31 mm²) |
JY [type] [class] [shell] [finish] [arrangement] [contact] [key] [suffix]
Example: JY27508E14F35SN — Box-mount rear-mounting receptacle, no backshell thread, shell 14, aluminum with nickel, arrangement 14-35, crimp socket contacts, key N
| Code segment | Options |
|---|---|
| Type | |
| Class | |
| Shell | |
| Finish | |
| Arrangement | |
| Contact | |
| Key | |
| Suffix |
Protective caps JY27510 (plug) and JY27511 (receptacle) are ordered separately.
96 standard layouts, viewed from the mating face of the pin insert. The arrangement number is written as shell size – layout (for example 25-35). The service rating sets the withstanding voltage (see specifications).
96 layouts
| Arrangement | Contacts | Contact sizes | Service rating |
|---|---|---|---|
| 8-03 | 3 | 3 × size 20 | I |
| 8-35 | 6 | 6 × size 22D | M |
| 8-44 | 4 | 4 × size 22 | M |
| 8-98 | 3 | 3 × size 20 | I |
| 10-02 | 2 | 2 × size 16 | I |
| 10-04 | 4 | 4 × size 20 | I |
| 10-05 | 5 | 5 × size 20 | I |
| 10-08a | 8 | 4 × size 20, 4 × size 22D | M |
| 10-35 | 13 | 13 × size 22D | M |
| 10-98 | 6 | 6 × size 20 | I |
| 10-99 | 7 | 7 × size 20 | I |
| 12-03 | 3 | 3 × size 16 | II |
| 12-04 | 4 | 4 × size 16 | I |
| 12-06 | 6 | 2 × size 12, 4 × size 20 | M |
| 12-06A | 6 | 2 × size 16, 4 × size 20 | M |
| 12-08 | 8 | 8 × size 20 | I |
| 12-08A | 8 | 4 × size 16, 4 × size 20 | M |
| 12-12A | 12 | 12 × size 20 | N |
| 12-16 | 16 | 3 × size 16, 13 × size 22D | N |
| 12-35 | 22 | 22 × size 22D | M |
| 12-98 | 10 | 10 × size 20 | I |
| 14-04A | 4 | 4 × size 12 | M |
| 14-05 | 5 | 5 × size 16 | II |
| 14-06A | 6 | 6 × size 16 | M |
| 14-13 | 13 | 4 × size 16, 2 × size 20, 7 × size 22D | M |
| 14-14 | 14 | 6 × size 16, 8 × size 22D | N |
| 14-15 | 15 | 1 × size 16, 14 × size 20 | I |
| 14-18 | 18 | 18 × size 20 | I |
| 14-19 | 19 | 19 × size 20 | I |
| 14-23 | 23 | 3 × size 16, 2 × size 20, 18 × size 22D | M |
| 14-32 | 32 | 9 × size 20, 23 × size 22D | M |
| 14-35 | 37 | 37 × size 22D | M |
| 14-97 | 12 | 4 × size 16, 8 × size 20 | I |
| 16-06 | 6 | 6 × size 12 | I |
| 16-06C | 6 | 4 × size 12, 2 × size 22 | I |
| 16-08 | 8 | 8 × size 16 | II |
| 16-14 | 14 | 6 × size 12, 8 × size 22D | N |
| 16-19 | 19 | 4 × size 16, 11 × size 20, 4 × size 22D | M |
| 16-26 | 26 | 26 × size 20 | I |
| 16-28A | 28 | 3 × size 12, 25 × size 22D | M |
| 16-35 | 55 | 55 × size 22D | M |
| 16-42 | 42 | 42 × size 22 | M |
| 16-99 | 23 | 2 × size 16, 21 × size 20 | I |
| 16-20 | 20 | 4 × size 12, 16 × size 22D | M |
| 18-11 | 11 | 11 × size 16 | II |
| 18-13 | 13 | 8 × size 12, 5 × size 20 | I |
| 18-17 | 17 | 2 × size 12, 15 × size 20 | M |
| 18-20 | 20 | 8 × size 16, 4 × size 20, 8 × size 22D | M |
| 18-22 | 22 | 7 × size 12, 15 × size 22D | M |
| 18-28 | 28 | 2 × size 16, 26 × size 20 | I |
| 18-30 | 30 | 1 × size 16, 29 × size 20 | I |
| 18-32 | 32 | 32 × size 20 | I |
| 18-35 | 66 | 66 × size 22D | M |
| 18-45 | 67 | 67 × size 22D | M |
| 18-53 | 53 | 53 × size 22 | M |
| 18-96 | 9 | 9 × size 12 | I |
| 20-11 | 11 | 11 × size 12 | I |
| 20-16 | 16 | 16 × size 16 | II |
| 20-24 | 24 | 24 × size 20 | I |
| 20-25 | 25 | 25 × size 20 | I |
| 20-27 | 27 | 27 × size 20 | I |
| 20-35 | 79 | 79 × size 22D | M |
| 20-39 | 39 | 2 × size 16, 37 × size 20 | I |
| 20-41 | 41 | 41 × size 20 | I |
| 20-61 | 61 | 6 × size 16, 55 × size 22D | M |
| 20-75A | 4 | 4 × size 12 | I |
| 22-02 | 85 | 85 × size 22 | M |
| 22-14 | 14 | 14 × size 12 | I |
| 22-21 | 21 | 21 × size 16 | II |
| 22-26 | 26 | 8 × size 12, 18 × size 20 | M |
| 22-32 | 32 | 32 × size 20 | I |
| 22-34 | 34 | 34 × size 20 | I |
| 22-34A | 34 | 4 × size 12, 16 × size 16, 14 × size 22D | M |
| 22-35 | 100 | 100 × size 22D | M |
| 22-36 | 36 | 36 × size 20 | I |
| 22-53 | 53 | 53 × size 20 | I |
| 22-55 | 55 | 55 × size 20 | I |
| 22-70 | 70 | 10 × size 20, 60 × size 22D | M |
| 22-86 | 86 | 16 × size 20, 70 × size 22D | M |
| 22-97 | 16 | 16 × size 16 | I |
| 22-99 | 11 | 11 × size 16 | II |
| 24-02 | 100 | 100 × size 22 | M |
| 24-04 | 56 | 8 × size 16, 48 × size 20 | I |
| 24-19 | 19 | 19 × size 12 | I |
| 24-24 | 24 | 12 × size 12, 12 × size 16 | I |
| 24-29 | 29 | 29 × size 16 | I |
| 24-35 | 128 | 128 × size 22D | M |
| 24-39 | 39 | 2 × size 12, 17 × size 16, 20 × size 20 | M |
| 24-43 | 43 | 20 × size 16, 23 × size 20 | I |
| 24-45 | 45 | 8 × size 12, 37 × size 20 | M |
| 24-61 | 61 | 61 × size 20 | I |
| 24-64a | 64 | 8 × size 16, 40 × size 20, 16 × size 22D | M |
| 24-69 | 69 | 10 × size 16, 15 × size 20, 44 × size 22D | M |
| 24-92 | 92 | 4 × size 20, 88 × size 22D | M |
| 24-93 | 118 | 8 × size 16, 110 × size 22D | M |
| 24-118G | 118 | 8 × size 16, 110 × size 22D | N |
Series II has the shortest, lightest shells. It suits equipment that is not exposed to high-level vibration or heavy sand and dust. For severe vibration choose the threaded Series III; for fast bayonet mating with a full-length shell choose Series I.
Series II shells are numbered 8 to 24, one step below the Series I and III sizes 9 to 25. The insert arrangements follow the same layouts, for example 24-35 with 128 size 22D contacts.
GJB599 Series II is built to GJB 599A Series II, the counterpart of MIL-DTL-38999 Series II. Send us your D38999 part number and we will propose the matching configuration and samples for your mating test.
Part number, drawing, pin-out or a short description of your application.
Our engineers match the configuration and reply with a drawing and quotation.
Samples are made to your order. Third-party testing to your specification is available on request.
You test the samples in your own equipment and approve them.
Production follows the approved sample configuration.
Send your part number, pin-out or drawing. An engineer will reply by email.
Straight and 90° · cable clamp 2.49–21.67 mm · 360° shield termination
38999 Series III type · shell sizes 9–25 · 184 insert arrangements
Plug and receptacle caps · shells 8–25 · chain, cable or cord lanyard
38999 Series I type · bayonet coupling · 127 insert arrangements