Sperian Biosystems PosiChek3 USB EP Enhanced Precision Test Breathing Machine

This Sperian, Biosystems PosiChek3, USB, EP Enhanced Precision Test Breathing Machine is used but in good condition.  The unit powers on but we are unable to test it further.  The power light illuminates as intended.  The calibration was good thru August 2010.  All switches and connection points are clean and in good condition.  The overall cosmetic condition of this set is good with the exception of minor scuff marks associated with normal use (see photos).  The hard case is in good condition and latches close properly.  All accessories are in good condition.  Please see list of included items below.  We do not have the expertise to conduct further testing.  However, this unit comes with a 30 day satisfaction guarantee.  Includes everything in the pictures and nothing else.