Sundial known as the Astronomical Ring Dial. Is elegant, portable and universal (can be used at any location/ latitude).It was one of most popular sundials of 17th and 18th centuries. It was principally employed as an equatorial universal solar quadrant. It is composed of a ring that can be adjusted to various latitudes, a meridian ring showing the latitude scale, a moveable hour ring and a central, grooved bar that is graduated for the months of the year and a perforated cylinder, which moves over this. It will indicate the solar local time.