Closure devices, and related delivery tools

A device (10) for sealing a passageway in a human heart, said step foramen oval free passage in a heart, the device comprising: a first anchor (12) adapted to be positioned proximate a first end of the passageway; including the first anchor (12) a plurality of arms (40) made of a first material; a second anchor (14) adapted to be positioned proximate to a second end of the passage; including the second anchor (14) a plurality of arms (50); a flexible elongate member (16) adapted to extend through the passageway and connect the first and second anchors (12, 14), the elongate member (16) of a second different first material being made in the second anchor ( 14) includes a cover (52) covering the spacing between the plurality of arms (50) and the first anchor (12) does not include a structure spanning the distance between the plurality of arms (40); the first anchor (12) is configured to engage a left atrial opening step, and the second anchor (14) is configured to fit into a step right atrial opening.