In the 1980's@ Advanced Technology Gear (ATG) steel rollingmill gear drives consisting of carburized pinions in mesh with very large@ weld fabricated@ high through hardened gears were introduced to improve capacity. Recently@ even the improvements obtained from these ATG gear sets were not sufficient to meet higher production rates and rolling loads. For greater load capacity ATG sets have been developed consisting of carburized@ hardened pinions in mesh with very large@ weld fabricated@ carburized and hard finished gears. Single and double helical gears of this type@ ranging in size from 80 to 136 inches pitch diameter have been implemented in several steel rolling applications. This paper describes the conditions that require the use of these gears and the technology required to design@ manufacture@ and@ especially@ heat treat@ these very special@ very large gear sets.