Picture: Team New Zealand unveiling

Both of Team New Zealand's new yachts, NZL-81 and NZL-82, were unveiled this afternoon at the Viaduct Harbour.

Both yachts had third appendages at the stern that looked almost as if they were part of the hull, but separated from it by a small gap.

These appendages are the "false hulls" or "Kiwi clip-ons" which have been the subject of widespread speculation for several weeks.

Team New Zealand principle designer Mike Drummond said the appendages provided more volume at the stern of the boat than would be allowed under America's Cup rules for just the hull by itself.

It meant the boats' sailing waterlines (which affect maximum speed) were a little bit longer.