SOI solaris oilfield infrastructure, inc. class a NYSE Metal Fabrications SSL sasol ltd. american depositary shares NYSE Oil & Gas Production SU suncor energy inc. NYSE Integrated oil Companies SUN sunoco lp common units representing limited partner interests NYSE Oil Refining/Marketing SWN southwestern energy company NYSE Oil & Gas Production THR thermon group holdings, inc. NYSE Industrial Machinery/Components TPL texas pacific land corporation NYSE Oil & Gas Production TTI tetra technologies, inc. NYSE Oil & Gas Production VET vermilion energy inc. common (canada) NYSE Oil & Gas Production VLO valero energy corporation NYSE Integrated oil Companies VOC voc energy trust units of beneficial interest NYSE Oil & Gas Production WRD weride inc. - american depositary shares NYSE Oil & Gas Production WTI w&t offshore, inc. NYSE Oil & Gas Production WTTR select energy services, inc. class a NYSE Oilfield Services/Equipment XOM exxon mobil corporation NYSE Integrated oil Companies YPF ypf sociedad anonima NYSE Integrated oil Companies