1 1/4" or 1 1/2" nail, I think. The head is about 3/8". Has a thick
(1/4"-3/8") paper washer on it. Galvanized.
Box says, "FURRING NAIL W/WAD."
They're used to keep chicken wire or lath away from the paper, so that when
the stucco is applied, the wire is surrounded by the stucco. Using them with
metal lath is a pain, but is possible.