A plurality of authentication servers belonging to different domains are connected to achieve a Single Sign-On using two cookies in two management systems. The upper part of the cell contains a removable thermic insulating cover placed just above the level of the electrolyte. The latching head moves to its rest or latched position by a combination of forces supplied by the compression member and attention member. The first driven member is configured to drive a first transfer gear, and the second driven member is configured to drive a second transfer gear for supplying torque to a bull gear associated with a rotor mast.