Thanks for the information.

These fenders are used to separate two ships, that may be at sea, as one takes cargo from the other. Lyme Bay on south coast of UK used to be one place where this occurred, used to lighten “supertankers” arriving from Middle East so allowing them to proceed to main European oil terminals like those in Rotterdam. Probably amongst others BP used this system. May have been due to ship size increasing faster than port facilities could cope and dates from 1970’s. others may know more, I was a junior engineer at the time I experienced “lightening”. Hope this is useful to explain things.

Great pic Captain Carlos-Takes me back to the BP tankers And Indian tankers I worked on in Scott's Greenock-Centre manifolds/Pump rooms etc!!!

You're speaking another language to me John ;-)

Could they be derricks for Yokohama type fenders used during lightening?

I've just seen her coming into Milford Haven and wondered why she has those T-shaped struts on her port side and more importantly, what are they ?