The d-MPBX is a MultiPoint Borehole Extensometer technology that enables up to 8 displacement sensors to be configured in a linear array. A single-rod design results in improved accuracy and digital signal processing to result in dramatically improved reliability compared to similar priced existing technology.
The d-MPBX is widely used to monitor underground excavations, open pit slopes, soil slopes, and can even be embedded in poured concrete slabs.
A technical note for the interpretation of d-MPBX data is available here