A line pin (also called a “brick pin”) is a metal rod usually with a pointed, leaf-shaped blade and a flat button head.
Line pins are typically found in pairs as they are most commonly used as anchor points for a brick line.
What are Line Pins used for?
Line pins are inserted into a brick course or staked into the ground, and a brick line (string) is wrapped around and stretched taut between the two points and used as a reference or guide line.
Because of the shape of a line pin you can insert and secure them between stones.
Or they can even be hammered directly into set mortar.