A fluid ejection device includes a substrate that defines a plurality of nozzle chambers. The portable device transmits a response message to the merchant machine. The method also includes transferring the reference frames of the video based on the transfer schedule for delivery to the mobile communication device over a wireless communication system and transferring update frames of the video for delivery to the mobile communication device over the wireless communication system without regard to the projected geographic path. The method and apparatus are applicable to any service that requires billing or other business response based on customer usage of the service. Rubber gaskets are associated with the respective endcaps, and are reliably secured to the endcaps by being snap fit into grooves molded into the plastic of the endcaps. The projection of the second member is received by the longitudinal groove.