The latches were Wissower a chalk formation in the Jasmund National Park on the island of Rügen and long time one of the most attractive tourist spots of the island.

On 24 February 2005, the two skidded up to 20 meters high main battlements into the sea. It has been about 50,000 cubic meters of chalk cut into the Baltic Sea and from the original formation of them left only a little. Cause was beside the surf, which constantly shapes the coastlines, the pressure of glacial deposits from the interior. Frozen precipitation water then blew after the onset of thaw from the rock masses. The demolition had been expected after a year on six cracks were discovered. One of these cracks had widened some time ago and about 1000 cubic meters of chalk fell one week before the big break into the sea. On the evening of 27 July 2010 there was again a violent demolition of chalk, which plunged about 150 tons of earth onto the beach.

The place is best for hikers to reach the delightful riverside walk through the high beech woods of Jasmund (about 2 km from the eastern outskirts of Sassnitz).

Often been wrongly assumed that the latches are Wissower presentation of the painting chalk cliffs of Rügen by Caspar David Friedrich was - this at the time of the creation of the painting but not yet exist, but were later due to erosion.

The name Jack comes from the Slavic klinu for angle or wedge, and refers to the appearance of the structure.