Two identical arch shape cross section chambers are joined together so that a dome shape part of one end of the chamber is overlapped by the opposing plain end of the second chamber. The roof system has a thermal energy absorbing product including a desiccant located between the roof deck and a roof barrier. A first attachment member allows the attachment of a chain to use the timepiece as a pocket watch, and a second attachment member comprises at least one recess arranged so that one bracelet end can be inserted therein, in the open position of the back, and locked by the back when it is closed. As long as the driver remains in the predicted tolerance band of the driving profile during the real drive, no re-calculation or change of the operating strategy is necessary. The memory blocks may be configured as content-addressable memory having arbitrarily adjustable tag and data widths. The deflected first and second light beams intersect between the optical deflector and the branching optical element, when projected on a plane perpendicular to the first direction.