This picture was taken by Johan Enqvist in the Lot region of France about six years ago, in February 2007. The dive marked the final exploration to the end of the famous "Fountain de Truffe" (to the terminal sump 13) by UK divers Rick Stanton and John Volanthen. Johan was there as a support diver, helping to ferry tanks between the sumps for the final push.
The temperature in this cave is 13 degrees celsius. Wetsuits are used due to the dry caving required in between sumps. A drysuit would not be practical due to the risk over overheating whilst working, and tearing the suit on the sharp rocks. Time in the cave would have been the better part of the day, it is a long and difficult dive due to all the transitions between dry caving and cave diving.
As far as Johan knows, this style of wing was used prior to the existence of production "doughnut" wings.