The sextant consists of circular polished brass plates with a lid that when fitted on the back of the instrument serves as the handle. The index arm is moved by a milled knob shipped in the upper plate. The sextant has one red index shade, which is moved by a lever, and no horizon shades. The index glass is non-adjustable and the horizon glass is moved by screws. Attached to the sextant is a single lens magnifier on a 65mm swivelling arm. It has a pinhole sight with a sliding red shaded shutter. The sextant has no box or case.

The instrument has a polished brass scale from -3° to 149° by 30 arcminutes, measuring to 135° (the digits are read from the pivot). The sextant has a brass vernier measuring to 1 arcminute, with zero at the left.