This Mine Recovery Outfit (M.R.O.) was built by C.E. Heinke & Co Ltd under commission to the Royal Navy to replace the Siebe, Gorman & Co. Ltd. Mine Recovery Suit (M.R.S.) in 1957. A total of eighteen of these state-of-the-art diving sets were built by Heinke for the Navy and the equipment was specially designed for investigating and recovering enemy marine mines. It was anti-magnetic and silent in operation which lead to another unique feature - voice communications, a technical challenge when combined with the neccessity to be magnetically and acoustically safe.
The equipment was designed for surface-orientated diving to a maximum depth of 30 fathoms (180 feet). It used appropriate mixtures of nitrox, depending on depth of operation and used a semi-closed-circuit breathing arrangement. To achieve the necessary gas flows and mixing at variable depths, it was provided with a unique venturi gas jet system. The diver did not have a mouthpiece or oranasal mask inside the helmet and breathed normally, as in a free-flow helmet.
The equipment was successfully trialled in Singapore and then placed in "War storage" - the strategy being that it could quickly be deployed in the event of any future conflict where the special diving equipment was required.
Interestingly, the introduction of the M.R.O. came in a period of "quantum leaps" in the diving technology deployed by the Royal Navy coinciding as it did with the development of the Transfer Under Pressure (T.U.P.) diving bell system aboard H.M.S. Reclaim. However, despite the undoubted quality and ingenuity of design, such a small order was insufficient to avoid Heinke's evenutal appointment with fate and the company merged with the ever competitive Siebe Gorman & Co. Ltd. a mere two years later, after over a century of leading-edge diving design and production.