Trimble S6 DR Plus 5" Robotic Total Station, MT1000 Active 360° Prism

S6 is equiped with Trimble's MagDrive servo technology silently spins the instrument through 180 degree in three seconds, while still providing ultra-fine control for precise pointing.
The Trimble S6 offers SurePoint technology.  SurePoint guards against the sinkage, vibration, and handling that can affect an instrument after setup.  Its automatic pointing correction monitors and corrects the effects of tilt axis and collimation, so you can measure with speed and confidence.
Direct Reflex (DR) technology from Trimble enables mearsurement without a prism even to extreme distances.
In Face 1 or Face 2, whether aiming manually or with the tracker, the Trimble S6 lets you measure exactly what you see.  The Trimble S6 optics by Carl Zeiss are fully coaxial for full measurement confidence.
Choose from active or passive tracking via the Trimble MultiTrack target.  Active tracking ensures the you always locate and lock on to correct target.  Active tracking also offers longer range, and the 360 degree active LED rings ensure accurate target tracking from any angle.
The Li-Ion internal smart battery provides six hours operating time in Robotic mode.  The smart battery also displays accurate battery discharge information.

The S6 experienced a couple of upgrades around 2010, including DR Plus EDM technology and optional VISION (digital camera). DR Plus replaced DR300+ and offers extended prism-less measurement range and faster measurement times (from 3-15 seconds down to under 5 seconds.) Trimble officially stopped production of the S6 in 2015, replacing it with: S5 and S7.

QUICK SPEC SUMMARY:

Available in 3 configurations: Servo, AutoLock or Robotic.
MagDrive™ electro-magnetic technology with SurePoint
DR Plus (Range without prism) . . . . . . . >1300 m “normal, 90% reflective surface”
Range with single prism . . . . . . . . . . . . >2500 m (8,202 ft)