The sextant has a polished brass frame and limb with a wooden handle. The tangent screw is 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 two horizon shades in red and green. Index-glass adjustment is made by a screw and on the horizon glass by a lever, knob and a milled clamping screw. Attached to the sextant is a threaded telescope bracket with perpendicular adjustment by a rising-piece and a milled knob. The telescope is 108 mm in length with an erect image. The sight-tube is 107 mm in length. The sextant is contained in a wooden keystone box, with a trade label in the lid for Norie and Wilson, 156 Minories, London (1882-99).

The instrument has a brass scale from -1° to 130° by 20 arcminutes, measuring to 120°. The sextant has a brass vernier measuring to 1 arcminute, with zero at the right.