The stay is a metal bar with holes that fit onto the peg, and allow the sash window to be held open in various positions.
[5] There are locks that can put a bolt through a hole in the stay to prevent the window from opening.
The tubes had the advantage of keeping out dirt and water, and having no protruding parts that could harm people.
[10] Another kind of friction stay is in the shape of a bent arm and can allow the window to open to 180°.
Common materials include steel, brass, zinc alloy, nickel and aluminum.
Four bar stays combine their function with a hinge, and can shift the window sideways as it opens.