Such wing means may in clude two radially opposite Wings and may in fact be replaced by three or more radial or substantially radial wings. It is only important that these wings extend until near the inner surface of the jacking part 5, or parts 4, 5, to slide between pairs of adjacent wire endportions when the jacking parts 4, 5 are passed over them. They will thus securely and positively impede a rotational or angular movement of the circular row of wire end portions if the handle member 10 is held against rotation as the tubular jacking part is being rotated to couple it 3 to the anchoring head, whereby the wires will be maintained in parallel, non-twisted relation.