A message gateway apparatus is provided for use in a web service system to process a message containing a request for a destination web service application, in which the message includes a plurality of events within a structured document conforming to a web service protocol and each event of the plurality of events has a name and a content thereof. The patch elements, typically of aluminium, preferably have a characteristic dimension no greater than about 500 \u03bcm and a spacing no greater than about 100 \u03bcm, while the emissivity of the combined surface and frequency selective surface is preferably no greater than about 0. The connector is a conductive body comprising a base section and a transverse section, the base section having a width greater than the transverse section and a length which extends beyond the transverse section. The positioning mechanism is provided between the case and the disk tray, and positions the second connector with respect to the first connector when the disk tray moves from the second position to the first position.