Wet-mate connectors can be mated and unmated while fully submerged underwater without requiring a dry environment. This is achieved through face-seal O-rings, oil-filled contact cavities, or wipe-clean contact surfaces that exclude water from the mated interface during engagement. All RV Power Group standard connectors are wet-mate capable.

Dry-mate connectors must be mated in a dry environment (air or controlled dry gas) before deployment. Once submerged, they rely entirely on the waterproof cable assembly and connector body to exclude water -- they cannot be safely disconnected underwater. Dry-mate connectors are typically used on fixed infrastructure (e.g., pressure housing bulkhead penetrators) that is not intended for routine in-water connection.

Which to choose?

• ROV tether, manipulator payload, hot-swap tooling: wet-mate
• Permanent pressure housing penetration: dry-mate penetrator
• Diver-deployed instruments: wet-mate
• Subsea Observatory node ports: wet-mate (ROV-deployable)