A passenger entertainment system for use on aircraft and other types of vehicles and methods for manufacturing and using same. The trailer coupler portion comprises a trailer hitch including a proximal hitch portion, a distal hitch portion, a hinge link connecting the proximal hitch portion to the distal hitch portion, and a hitch locking mechanism adapted for locking the distal hitch portion in position with respect to the proximal hitch portion. The second layer automatically offers the required resource together with a condition for use of those resources. The clutch is a hydrodynamic clutch having a primary wheel and a secondary wheel, which jointly form a working chamber that can be filled with a working fluid, and is provided with a working fluid supply system associated with the clutch and with means for influencing the transmission behavior of the hydrodynamic clutch. The transmitter transmits either information representative of the measured physical dimension or cutting dimensions. If the measured voltage exceeds a predetermined amount, a switch is operated to electrically connect the two points.