General Tools DSM20 USB Digital Sound Level Data Logger Monitor environmental and industrial noise along with decibel levels during acoustics design, sound system setups and OSHA compliance testing Just one button starts or stops data logging without a PC; the LCD displays real time sound level along with min, max and average displays The simple plug-and-play USB 2.0 interface is easy to use, no fussing with cables, cradles or docks The datalogger has a large storage capacity offering the ability to store, track and download 32000 sets of data into Excel-Format Comes with PC software, USB extension cord, a DC3.6V non-rechargeable lithium ion battery and a 1 year limited warranty