Why not add a backup neurofeedback device to your inventory so that if the main device goes down, you won't have to delay client treatments. 

Although the Neurobit Optima 4 is no longer being sold by Neurobit Systems, I confirmed that they are still supporting it, i.e., repairing it when necessary.  The devices comes with everything shown in the photographs.

Did some additional cleaning on the device and and white appearance on the right hand side is me trying to get as much small debris out of the crack as possible.  

One other thing that I forgot to mention is that I made one minor mechanical modification to the device:  I noticed that if batteries were left in it for an extended period of time that the silver clips(negative side) would no longer make good contact.  I added small springs, typical springs that you find in most devices that use batteries(AA,AAA), behind those clips to insure that no matter how long the batteries where left in it, they would always spring back to life like it was the first time.

Neurobit Optima™ 4 / 2

 Portable equipment for neurofeedback, biofeedback & physiological data acquisition

Highlights

•       4 versatile, low-noise channels enabling measurements of voltage, conductance, resistance and temperature signals. (NO-2 model has

2 channels.)

•       function of each channel is specified by a user (e.g. 4 x EEG, or EEG + EMG + GSR + TEMP, or 2 x EEG + 2 x EMG etc.) 

•       built-in test of electrode-skin  impedances and input circuit continuity,

•       independent reference inputs for each channel,

•       16-bit resolution of measurements,

•       1% accuracy of voltage measurements, 

•       output sample rate up to 2000 sps,

•       oversampling (primary sampling rate up to 8000 sps),

•       selectable frequency characteristics enable to minimize signal delay or maximize frequency bandwidth,

•       high immunity to electrical interferences,

•       option of active shielding of sensor cables to reduce movement artifacts,

•       configurable filter of power mains interferences (50/60 Hz or off),

•       full galvanic isolation of the subject’s body,

•       wireless connection to a computer,

•       interoperation with many computer applications making possible flexible signal processing and visualization (also in real time), as well as storage in a computer,

•       application programming interface (API),

•       device extension with digital signal processor (DSP) executing client defined algorithms (custom-made option),

•       2 AA battery powered,

•       long work without battery replacement,

•       indicators of battery, wireless link and measurement input states,

•       small size and weight,

•       belt clip enabling to wear the unit,

•       remote firmware upgrade