The Fathom Tether is a high quality tether cable designed specifically for ROVs and other subsea applications. It is neutrally buoyant, has 300-350 lb breaking strength, and is embedded with water-blocking fibres to seal any leaks. With diameters of 4mm and 7.6mm, these tethers are slimmer than the vast majority of comparable ROV tethers.

The tether carries one or four unshielded twisted pairs (UTP) of 26AWG wire. These pairs are coloured and arranged in the same fashion as a Cat5 networking cable including cross-talk resistance. A pre-installed Binder 770 plug makes it easy to connect to the FXTI and Fathom Spool. A cable penetrator is installed at the other end to interface with the BlueROV2 or any of our watertight enclosures.

The slim tether really shines when it comes to its size. Its slim profile makes it ultra low-drag, making it ideal for deep dives, high current dives, and long distance dives where the drag from the tether is really noticeable. The size also makes it incredibly portable and easy to handle. A hundred meter tether weighs just 3 lb (1.4 kg) and can be managed by hand very easily.

Since the slim tether only has two wires, it can only be used for the primary communication of the BlueROV2. There are no spare twisted pairs when using this cable, which means that it is not compatible with applications where you need extra tether pairs.

The core of the cable contains Kevlar strands for strength and Dacron fibres for space filling. Both fibres are impregnated with waterblocking compound to block any leaks caused by nicks or rips in the cable. The high-visibility yellow polyurethane foam jacket resists abrasion and provides neutral buoyancy.

The stiffness of the cable is designed to be flexible enough to give plenty of freedom to your ROV, but stiff enough that it does not become tangled easily.

The capabilities of this tether are meant to provide design flexibility and a wide variety of uses. Pololucarries the 3 position 0.1” (2.54mm) Crimp Connector Housings and male crimp pins that may be used for connecting your own devices to the spare tether terminations.

We also have this cable available by the meter with no terminations at either end.