An armrest unit for a passenger seat includes an armrest base body forming an armrest surface, and a suspension unit which is disposed underneath the armrest surface and which has at least one spacing means. In the methods, dummy recess regions may be formed between cell recess regions and a peripheral circuit region. Three types of VLANs internal to the switch are defined, \u201cprimary\u201d VLANs, \u201cisolated\u201d VLANs and \u201ccommunity\u201d VLANs. This circuit ensures a relatively low impedance for a PA that is implemented within chip thereby providing for improved performance. A C-shaped clamp member secures the shell to the platform of the spar and form cooling air channels to discharge the spent cooling air into the fillet region of the blade.