A stent graft (2) has a fenestration (10) surrounded by an inner edge, and the inner edge (7) further surrounded by an outer edge (9) of larger diameter. A shaped protrusion (4) of semi-rigid graft material spans the distance between the inner edge and the outer edge connecting the two edges. The shaped protrusion has a surface area larger than the plane of the tubular body between the edges and therefore has excess material which allows the inner edge and the fenestration to move within the circumference of the outer edge. The shaped protrusion may also form a semi-rigid dome.
