Anodised brass three-circle pattern frame, wooden handle, which has been signed on the limb 'Frodsham & Keen, Liverpool'. The brass limb has an inlaid silver scale from -5° to 150° by 10', measuring to 133°.

The silver vernier measures to 5'', with zero at the right. There is a tangent screw and clamp screw on the back of the index arm. Index glass adjustment is by screw, and the horizon glass by capstan screws. The sextant has four shades (blue, orange, red, grey) and three horizon shades (red, orange, blue). There is a magnifier on an 80 mm swivelling arm with a frosted glass shade. The telescope bracket is in two parts, and has perpendicular adjustment by clamp with milled knob. The sextant also has a telescope (83 mm), with an erect image; telescope (186 mm) with inverted image; two pairs of parallel wires set perpendicular to each other; sight-tube (80 mm); adjusting pin; and a shaded eyepiece (red). The radius is 6 3/16'' (155 mm).

The instrument is fitted in a square wooden box with felt lining. One part of the instrument is missing (probably an eyepiece with variable shades). There is a brass plaque on top of the case lid is inscribed 'H.M.S. "CONWAY" / THE / BROCKLEBANK PRIZE / Presented to / J.D. CAMPBELL / JULY 1904'.