Lockwood Gen 6 Restricted profile
This one's set up for a 334/45 padlock but it can also be put in a 570 oval/euro type cylinder being a hold back plug.
(Like most of the padlock plugs)
http://i1105.photobucket.com/albums/h346/sideshowmick/20101029_01.jpg
http://i1105.photobucket.com/albums/h346/sideshowmick/20101029_02.jpg
http://i1105.photobucket.com/albums/h346/sideshowmick/20101029_05.jpg