Cobalt Series Cable, Single-ended


Polyurethane-jacketed cable with Cobalt Series plug and locking sleeve on one end.  For use with Cobalt Series Bulkhead Connector (sold separately).  Rated to 600 m depth.  Available with 3, 4, 6, or 8 conductors, and in a standard 1-meter length or custom lengths from 0.1 to 2.0 meters.  Patent Pending.

SKU: N/A Category:


The Cobalt Series of dry-mate underwater connectors and cables from Blue Trail Engineering sets a new standard for miniature waterproof connectors. Cobalt connectors offer the same reliability as larger subsea connectors, but at a fraction of the cost. With 316 stainless steel shells and PEEK inserts, they withstand long-term use in seawater at depths up to 600 meters. In spite of their compact size, Cobalt connectors carry up to 12 amps on each of 3 pins, 20 amps on each of 4 pins, 5 amps on each of 6 pins, or 0.5 amps on each of 8 pins. Connector shells are keyed and feature a scoop-proof design, allowing them to be mated blind with no possibility of pin damage.


Cobalt Series cables feature a simple, robust seal between the cable jacket and connector shell that eliminates the need for overmolding. A second hermetic seal between the connector pins and the connector shell provides redundancy. Because Cobalt connectors do not require overmolding, they cost less than traditional molded cables and connectors and eliminate the danger of leakage due to cathodic delamination. A simple, proven O-ring seal between the male and female connectors makes Cobalt connectors both easier to use and more reliable than wet-mate connectors. Perfect for space-limited applications, Cobalt connectors take up a fraction of the volume of the industry-standard Micro-Circular connectors.


Cobalt cables are available with 3, 4, 6, or 8 conductors, and in a standard 1-meter length or custom lengths from 0.1 to 2.0 meters. Cables are available in various end termination configurations:

  • Both ends terminated with Cobalt connectors
  • One end terminated with Cobalt connector, the other end unterminated
  • One end terminated with Cobalt connector, the other end terminated with Blue Trail Engineering Simple Penetrator


COBALT CABLE MUST BE USED WITH COBALT BULKHEAD CONNECTOR (sold separately).  The Cobalt bulkhead connector fits in the same 10-mm hole as Blue Robotics penetrators, making quick-connect and quick-disconnect possible with Blue Robotics enclosures, thrusters, lights, grippers, and other accessories.

Additional information

Weight N/A
Dimensions N/A

1, Custom (0.1m – 2.0m)

Pin Count

3-pin, 3-pin Power, 4-pin, 6-pin, 6-pin Hybrid, 8-pin

Technical Information


Depth Rating

600 meters

Operating Temperature

0° C to +50° C


Maximum voltage

300 V

Rated current

3-conductor version: 12 amps

4-conductor version: 20 amps

6-conductor version: 5 amps

8-conductor version: 0.5 amps

Wire size

3-conductor version: 18 AWG

4-conductor version: 16 AWG

6-conductor version: 22 AWG

8-conductor version: 24 AWG

Wire stranding

3-conductor version: 19/30

4-conductor version: 19/29

6-conductor version: 19/34

8-conductor version: 7/32


Bulkhead connector shell

316 stainless steel

Bulkhead connector insert


Bulkhead connector pins


Cable connector shell

316 stainless steel

Cable connector insert


Cable sockets


Cable jacket

95A UV-stabilized polyurethane

wire insulation

3-, 4-, and 6-conductor versions: ETFE

8-conductor version: polyolefin

O ring


Locking sleeve



Bulkhead connector threads

M10 X 1.5

Bulkhead connector hex

16 mm

Locking sleeve threads

M16 X 1.5

Cable outer diameter

3- and 6-conductor versions: 6.4 mm

4- and 8-conductor version: 8.0 mm