The Aries class superlifer was conceived as a replacement for the earlier Vanguard class which had demonstrated severe deficiencies. Originally designed to aid in deep space construction work, the Aries class proved so versatile that it was also employed in asteroid mining, deep space surveying, cargo haulage and rescue operations. It proved extemely popular with its two-person crews and the companies that operated them for its unsurpassed safety record, reliability and extreme ruggedness. Aries class ships employed a high strength towing cable to enable it to haul outsized loads, and later versions came with an in-flight refueling boom that was operated by the second member of the crew, thus enabling superlifters to refuel smaller vessels in deep space. Over four thousand superlifters or "grip ships" were built over a twelve year period beginning in 2107. In the thirty years since superlifter construction ceased several specialized vehicles were created to replace them, but even now, several hundred can still be found working around the asteroid belt.