The Emcan Astro EM31 Pro is a Harmonic Drive Alt-Az/Equatorial mount that is powered by the open source OnStep telescope control system, providing USB,2.0, WiFi and Bluetooth connectivity, easy connection via Ascom, INDI and the ZWO Asiair. The EM31 Pro features both USB and 12v 5A DC passthrough ports in the declination head, allowing the mount to be controlled via an onboard computer without the risks of cable snags, as the main ports of the mount are static to the telescope equipment, which is also great for the overall look of the rig once it is set up. The mount is driven by Nema 42 motors and type 17 harmonic reducers for both the RA and Dec axis providing 30nm of torque. Due to the slimline design of the mount body, the base of the dovetail saddle is only 9.4cm from the RA axis, allowing this light weight, 4kg mount to have an impressive payload capacity of 15kg without a counterweight, or up to a maximum of 20kg when a counterweight is used. (Payloads calculated with equipment center of mass at a distance of 20cm from the RA axis. Perhaps one of the most innovative features of this mount is the the polar alignment adjustment mechanisms for both the altitude and azimuth. A patented design allows polar alignment to be adjusted without the requirement for locking the axis afterward, meaning there is absolutely 0 chance of a locking mechanism bumping  the mount out of alignment.