all kinds of dished heads /dish end / semi elliptical head/for pressure vessels, tanks,boilers all shapes of dished heads / dish end/semi elliptical headmaterial: SA516 Gr70 ,16MnR,16MnDR,P355CL1 , ss304L,316L, etcStandard: AMSE VIII Div-1 ,UG81 semi elliptical dish