A system for synchronizing data after they are collected and stored locally in sensor units in a distributed sensor system, so that wired or wireless communication is not required during a data-collection session. A first mounting tab and a second mounting tab extend from the central region at an angle. A bottom face of the stop projection for engaging with the stop groove is an inclined face that rises toward a front end of the stop projection. Heat from the LED die can flow through the heat sink base to the heat sink, from which the heat can be dissipated. The system includes a data apparatus with customer identification, and a reader that determines the customer’s pre-determined order and payment method by information provided to the reader on the data apparatus or by accessing a database that has the information and can be accessed by determining the customer identification. If the wideband signal is acquired, the narrowband filter hold time can be set to a predetermined minimum time limit.