... ,mine,railway,agriculture,forester,climbing.etc) 1. Portable IT and Digital Device:laptop,MP3,PMP,CD,Portable DVD,Portabe Printer,Portable ... scanner,Portable Projection Instrument, Portable Acounstics,Transmitter-receiver,Video Tape Recorder,Portable Video Recorder,etc 2.Portable Testing Machine: Computation and Testing Instrument ...