hurricane conditions and chemically corrosive environments the inner modules 23 can have any one of a variety of shapes in a preferred embodiment the modules and housing are rectangular in shape however they can be cylindrical particularly if the inner module is an electronic module if rectangular inner module and housing shapes are used it is envisaged that the inner module will have two sloping angled portions or arms in between the arms which extend and then a handle can be disposed between the arms for engagement by an rov the slope of these angles may range from 90 to 180 degrees which enables ease of insertion of the inner module 34 into the outer housing 23 however it is fully within the scope of the present invention that the inner modules could be of different shapes for example the outer housings 23 and inner modules could be cylindrical pyramidal conical cubical square pyramids or other geometric shapes the inner modules preferably have at one end various kinds of attaching means that enable the pulling or pushing of the inner modules into the outer housings a handle 74 is shown in fig1 and can be used effectively on the inner module particularly by an rov when a human hand can not be used with the handle preferably the handle 74 is of a shape such that it can be used by a rov or by a suited diver or a one atmosphere diving suit which acts like a manned vehicle needing to use a hook or similar non human device to engage and re engage the inner module in the housing it is also possible.