The fourth hardware revision is a four-site stimulator like the CM-3, however, it is not magnet compatible. It uses the same underlying VCA technology as the CM-1 and CM-2, but the coils are 10 times stronger. Position control was also reintroduced for this model, making control over the probe tips more precise than any previous revision. Combined with the stronger coils, the CM-4 is capable of higher command signal fidelity even while driving a significant load for an extended period of time. The CM-4 currently leveraged by Dr. Tommerdahl's Laboratory for Neurosensory Diagnostics for all human somatosensory testing.