The TCRP1203 +R400 3" Robotic Total Station has an angular accuracy of 3". Leica specs are indeed conservative as the instrument meets +/- 1.5" specifications for a total error of 3". Most other comparable total stations of different brands are specified at +/- 3". With Leica, you can expect to close with greater accuracy and better than 3" of error. It comes with a PinPoint EDM accuracy of 2 mm + 2 ppm with a range of 3,000 m to a single prism. Fully Robotic PowerSearch finds standard prisms in seconds no matter where they are. Automatic Target Recognition System takes over once PowerSearch has found the prism and snaps the instrument to the center of the prism. With ATR, you only need to point roughly with the optical sight; the TPS1200 does the rest and finds the center of the prism. The TCRP1203 +R400 3" comes standard with fully robotic motors that enable the instrument to Auto Lock and track moving prisms and remains "locked" onto the prism. The On-Board Software includes: Survey, Stakeout, Cogo, Determine Coordinate System. The TCRP1203 +R400 3" comes with the Leica CS15 Field Controller for one-man operation. The instrument utilizes the RH16 Integrated Radio Handle for communication with the CS15 Field Controller.