[3] It is 74 feet (23 m) in height and hexagonal in plan; mounted on seven piles forming a steel lattice and originally painted red.

Additional storage space was provided in the 'inverted pyramid' beneath the dwelling, which was accessed by a ladder from the gallery.

[6] The light flashed red once every 30 seconds; it was lit using Argand lamps and reflectors mounted on a revolving triangular frame, with a pane of red glass mounted in front of each reflector.

[6] It also had a fog bell, which sounded once every ten seconds in bad weather; like the lamp mechanism, it was driven by clockwork.

[12] It remains in use as an automated weather station by the Port of London Authority,[4] and marks the northern limit of their jurisdiction.