Swing-arm rods use hinged arms that rotate (up to 180°) so curtains swing out of the way when doors or windows open. This lets you mount the rod above inward-opening openings without obstructing their operation.
Adjustable lengths vary widely: short swing-arm spans around 14 inches up to large telescoping bay rods that extend to about 144 inches, with several intermediate extendable sizes available.
Compatible styles include curtains hung with rings, panels, pockets, grommets, back tabs, tab tops, and clip rings.
Double bay-window rods support layering by allowing a heavier decorative curtain on the front rod and a lighter sheer on the back rod. One listing specifies adjustment ranges: a center-adjusting measurement from 28 to 72 inches, and side adjustments from 22 to 37 inches on both sides.
Curved or wraparound rods let curtains follow the window curve or wrap flat against the wall, reducing gaps at the window edge and improving light blocking compared with straight rods.