The sextant in case measures 6" x 6" x 3.25". This sextant is an exact replica of a mid 19th C. working sextant. Intricate and semi-functional, it has all the pieces needed to shoot the sun. A sextant defined latitude. A clock defined longitude. Pocket sextants were used by explorers to define location and direction. Defining the angle of the Sun and Stars with the horizon was an important way to navigate and survey. A beautiful intricate little instrument with an interesting and ancient history.