RMG-3-MP In-Line Rubber Molded Connector - 3 Pin Male — neoprene rubber molded in-line underwater connector, 3-contact (1×#14 + 2×#16), rated 20,000 PSI / 600 VDC. Gold-plated copper alloy contacts. For ROV, diver umbilical, subsea lighting, and marine instrumentation systems.
The RMG-3-MP In-Line Rubber Molded Connector - 3 Pin Male is a precision-molded in-line underwater connector from the Rubber Molded Series — one of the most proven connector platforms in marine and subsea engineering. The entire connector body is formed from a specially compounded Neoprene (Chloroprene) rubber in a single-shot injection moulding process, creating a seamless, jointless waterproof housing with no machined interfaces, no adhesive bonds, and no potential leak paths between dissimilar materials.
Rated to 20,000 PSI (1,379 bar) in the mated condition, this connector maintains full electrical performance from the surface to the deepest ocean trenches. The 3-contact configuration (1×#14 + 2×#16) combines power and signal conductors in one compact body — eliminating the need for separate power and data connectors on ROV systems, diver umbilicals, and subsea instrument packages.
| Parameter | Specification |
|---|---|
| Contact Configuration | 1×#14 + 2×#16 |
| Pressure Rating (mated) | 20,000 PSI (1,379 bar) |
| Voltage Rating | 600 VDC (higher voltages available on request) |
| Contact Material | Copper alloy, hard gold plate per ASTM-B-488 |
| Body Material | Special Neoprene (Chloroprene rubber), integral moulded |
| Seal | Buna N 70 Durometer O-Ring, silicone grease lubricated |
| Standard Cable | 18/3SO, 18" length, Neoprene jacket |
| Operating Temperature | -55°C to +85°C |
| Depth Rating | Full ocean depth (mated pair) |
| Series Compatibility | Mates with RMG bulkhead connectors (XSG-BCL, RMG-BCL, XSG-PBCL) |
Metal-shell subsea connectors seal through multiple discrete O-rings at machined interfaces — each interface is a potential leak site if the O-ring is damaged, the machining tolerance is exceeded, or the seal face is contaminated. Neoprene integral moulding eliminates all interfaces: the rubber is the waterproof housing. There are no grooves to clean, no faces to inspect, and no O-rings to replace between dives.
At 20,000 PSI (1,379 bar), rigid connector shells must resist the full hydrostatic pressure load through mechanical stiffness — requiring heavy wall sections and large bolt patterns. The neoprene body compresses elastically under hydrostatic load, transmitting pressure uniformly into the rubber mass rather than concentrating stress at mechanical features. This elastomeric pressure equalization improves the seal at greater depth — the connector actually becomes more waterproof under higher pressure.
Metal connector shells are rigid — they transmit cable bending loads directly to the mating interface, creating levering forces on the O-ring seats. The neoprene body flexes with the cable, absorbing bend transitions smoothly without concentrating stress at the connector body. This flexibility reduces fatigue failure at the cable/connector junction — a common failure mode in ROV operations where tether cables are repeatedly coiled and uncoiled on drums.
Rubber moulded connectors are significantly less expensive than machined metal alternatives with equivalent depth rating — enabling operations to stock spare connectors for immediate field replacement without budget impact. The simplified mating procedure (O-ring face seal, hand-tight locking sleeve) also reduces dive preparation time compared to torque-wrench-tightened metal connector systems.
| Accessory | Part | Function |
|---|---|---|
| Male Locking Sleeve | G-MLS-D | Prevents accidental unmating of male plug under load |
| Female Locking Sleeve | G-FLS-D | Prevents accidental unmating of female socket under load |
| Male Dummy (LP) | RMG-MPD-LP | Protects female socket face; rated <4,000 PSI unmated |
| Male Dummy (HP) | RMG-MPD-HP | Protects female socket face; rated 4,000–20,000 PSI unmated |
| Female Dummy | RMG-FSD | Protects male plug face; rated 20,000 PSI unmated |
| Bulkhead (glass-epoxy) | XSG-3-BCL | Panel-mount bulkhead; mates with RMG-FS in-line |
| Bulkhead (316 SS) | RMG-BCL | Metal bulkhead; 3/4-16 UNF thread; 20,000 PSI |
| Bulkhead (non-metallic) | XSG-PBCL | 1/2-20 UNF; face O-ring seal; 5,000 PSI |
Before mating, inspect both connector faces for contamination, debris, and O-ring condition. Clean the face seal O-ring with a soft cloth and apply a thin film of silicone grease (DC-4 or equivalent) — the grease both lubricates the O-ring for smooth mating and displaces any water film that could be trapped under the seal. Never use petroleum-based grease — it degrades Neoprene and Buna N rubber over time.
Align connector faces squarely and push together with firm, steady pressure until the faces are fully seated — the O-ring should compress uniformly with a slight increase in resistance at full seating. Install the locking sleeve by hand until finger-tight — do not use tools to over-tighten. The locking sleeve prevents rotational unmating; it does not increase the face seal compression. A hand-tightened locking sleeve is fully functional for 20,000 PSI applications.
After each dive, unmate the connector, rinse both faces with fresh water, inspect the O-ring for cuts, abrasion, or compression set, and check the gold contacts for green verdigris (seawater ingress indication). Replace any O-ring showing permanent deformation or damage before the next dive. Store unmated connectors with dummy plugs installed — never leave a connector face unprotected between dives.
In stock for immediate dispatch. Custom cable length, jacket material (TPU, polyurethane, FRNC), and WOC (field-terminate) versions available. Matching bulkhead connectors, locking sleeves, and dummy caps supplied from the same source.
20,000 PSI | 600 VDC | 3-contact (1×#14 + 2×#16) | Neoprene moulded | Gold contacts
