A paint brush is an item used in construction.
They are used to plaster a player constructed wooden wall.
A plastered wall, whether it's player constructed or not, can be painted using paint and the paint brush. Symbols can also be painted on more surface types than just plastered walls, such as on a wooden sign.
They are used to paint a plastered wall.
Paint brushes are usually found in crates.
From items.txt (Project Zomboid directory/media/scripts/)
Weight = 0.2,
Type = Normal,
DisplayName = Paint brush,
Icon = Paintbrush,