The Toknav TMC20 is a machine-control guidance kit for excavators that uses multi-constellation GNSS (BeiDou/GPS/GLONASS/Galileo) positioning combined with an inertial measurement unit and tilt sensing to give the operator centimeter-level bucket and depth guidance in real time. A high-brightness in-cab display shows graphical and numerical dig/fill data and can auto-calculate excavated area, helping reduce over-digging and rework on trenching, slope-trimming, and grading jobs. It mounts to the excavator via a machine-specific bracket, so bracket compatibility should be confirmed per excavator model.