A blood vessel occlusion device comprising a plurality of legs having a deployed state wherein each of the plurality of legs is angled outwardly toward a vessel wall and a delivery state wherein the plurality of legs are sized and shaped for pushing into a target blood vessel and substantially in parallel to a common longitudinal axis. Each leg has an anchoring tooth at a distal end thereof and a gripping point formed therealong. Each leg switches from deployed state to delivery state by a retention element and maintained in delivery state when said retention element is supported by the gripping point.