The present invention relates to a downhole expandable metal tubular having an axial extension, to be expanded in a well downhole to abut against an inner face of a casing or a borehole, comprising a first section having a first outer diameter, two circumferential projections having a second outer diameter which is larger than the first outer diameter, a second section arranged between the two projections, each projection having an inclined face tapering from the second outer diameter towards the second section, wherein the second section has a third outer diameter which is smaller than the first outer diameter in an unexpanded condition, and a sealing element is arranged between the projections opposite the second section, so that during expansion the second section bulges more radially outwards than the first section, forcing the sealing element radially outwards. Furthermore, the present invention relates to an annular barrier, a downhole completion and a sealing expansion method.