It’s a shame how 5th Avenue is deteriorating so much, lamppost-wise. At one time there was an unbroken string of these Twins (in 2 different species, admittedly) from Washington Square to Central Park. Now, just four remain. We lost this one recently.
Even 5th Avenue’s set of twin Deskeys, special editions debuting in 1965, are gradually being attritted out, as parts are no longer available.
Soon, 5th Avenue will have a motley mishmosh of straight mast and cobra neck octagonal posts, and boring 34th Street Partnership posts, just like the other midtown avenues. Pity.