The repeating circle consists of a circular polished brass frame, with a wooden handle on a fixed U-shaped bracket. A detached second handle can be screwed in the bracket on the front of the frame. The limb with the scale is on the back of the frame and can be moved 360° round by hand; it is secured by two clamps, and by the index arm clamp. The index arm carries the index glass and the telescope bracket and horizon glass are rigidly mounted on the frame. The double-ended tangent screw and a clamping screw are on the back of the index arm. The instrument has three index shades, two red and one green, and three horizon shades, two red and one green. Index-glass adjustment is made by two screws and on the horizon glass by a screw and a capstan screw.

Attached to the circle is a magnifier on a 55mm swivelling arm. There is also a threaded telescope bracket in two parts, fitted for correcting collimation error. It has perpendicular adjustment made by a rising-piece and a milled collar. The telescope is 172 mm in length with an inverted image and four cross wires. An extra drawtube is 67 mm long with four cross wires. A second telescope is 68 mm long with an erect image. Accompanying the instrument is a sight-tube, which is 92 mm in length, a red shaded eyepiece, an adjusting pin, a screwdriver, and a magnifying glass.

The instrument has a polished brass limb with an inlaid silver scale from 0° to 720° by 20 arcminutes. The repeating circle has a silver vernier measuring to 15 arcseconds, with zero at the right, and one silver sighting line.

The repeating circle is contained in a square fitted wooden box lined with green textile and containing trade labels for William Heather, 157 Leadenhall Street (1793-1812), London, and for H. Hughes, 59 Fenchurch Street, London (1859-75).

The U-shaped bracket was recommended by Mendoza Rios, and according to him first applied by Troughton.