A set of flat identifiers are received, and a locality of reference cue determined. Familial features are included for easy setup and control. However, coherent light sources may cause serious and unrecoverable injuries to human eyes. When the covering lid rotates to a covered position, the sheltering portion extends beyond a front edge of the holding seat. The composition meets or exceeds the standards of both the ILSAC GF-4 and the General Motors GM4718M specifications. Also disclosed is a dehumidifier having the heat exchanger.