For prestigious entrances, Ponzi proposes the type of curved sliding doors with three models: Rondina, Ronda with a circular shape and lowered arch with variable radius. The curved sliding version finds its use in the entrances that require characteristics of image and design such as hotels and accommodation facilities. Curve doors can be combined with a linear sliding door to create an entrance compass. The path thus created is linear and allows users a smooth transit. The two entrances open and close one after the other, also by consent or access control, eliminating passage and drafts. In case of need for entry authorized to escape. The lowered arc type is used, to which the T.O.S. device can be applied A special certifying body guarantees its suitability for use for the emergency exit. The mobile curved doors are broken by the simple manual push in the direction of the exit, even during normal sliding. The automatic Lowered Arch T.O.S. is used as an elegant door, as an alternative to revolving doors.