Door viewer, 220 degree

A standard 160° viewer leaves a blind wedge on both sides of the door — which is exactly where someone stands if they do not want to be seen. A 220° lens covers the full doorstep including the wall either side, and the wide-angle glass is optically corrected rather than a plastic fisheye that turns a face into a smear.

Solid brass barrel with a privacy cover on the inside, for 14 mm bore in doors 1-3/8 to 2-1/8 inches thick. Fits the standard viewer hole in most existing doors without redrilling.

Fitting and care. Measure the existing bore first: 14 mm is the common size but older doors are often 12 mm and will need opening out with a spade bit and a backing block to stop the far face splintering. Set the height for the shortest adult in the house, not the tallest. Keep the inside privacy cover closed as habit — a lit hallway behind an open viewer tells someone outside that a room is occupied. Clean the outer glass occasionally; a filmed lens in low light is the same as no viewer.