Featuring a simple strong and attractive design the new ultra 410 is the ideal entry level d lock and complements the super ultimate and ultimate line up its simple design conceals a number of high tech advancements in security including a new double layered key with decoy cuttings and a cylinder with special wafers which make this lock virtually impossible to pick with conventional methods every variant is sold secure silver certifiedthe 12mm thick double bolted hardened steel shackle extend