We have a Cadwell Sierra Wedge EMG/NCV/SSEP systems with a Toshiba Windows XP laptop, preloaded with Cadwell Wedge version 2.2.2C program All settings are restored to factory defaults. In addition to the instrument base & laptop, there's a 2 channel Wedge preamplifier, interface cable, Sierra Wedge electrical stimulator, footswitch, carrying case, surface electrode kit, and operator's manual. A Cadwell stand is available This system was used minimally by a solo practice. It's in excellent condition. For an additional $495, we can set up the Sierra Wedge with a Windows 7 laptop preloaded with Sierra XP program.