The sextant has a polished solid 0.25 inch thick brass frame with a detached wooden handle. The tangent screw is located on the front of the index arm and the clamping screw is on the back. The sextant has three shades, two red and one green, and three horizon shades, two red and one green. Index- and horizon-glass adjustment is made by screws.

Attached to the sextant is a magnifier, which has now been detached, on a 55mm swivelling arm. There is also a threaded telescope bracket with perpendicular adjustment made by a rising-piece and a milled knob. The telescope is 133 mm in length with an inverted image and four cross wires. A second telescope is 59 mm with an erect image. The sight-tube is 57 mm in length and there is a silver reflector fitted into the index arm clamp to throw light on the scale. The sextant is contained in a fitted mahogany box.

The instrument has a polished brass limb with inlaid silver scale from -2° to 148° by 20 arcminutes, measuring to 135°. The sextant has a silver vernier measuring to 30 arcseconds, with zero at the right.