VEVOR Chimney Sweep Kit 30FT Length, Chimney Brush Kit with 9 Nylon Flexible Rods, Rotary Chimney Cleaning Kit Driven by Drill, Chimney Cleaning Tool Kits for Sweeping Fireplace Flue

Our chimney brush can be used to high efficiently clean many kinds of flues, the shapes does not matter at all; if your chimney pipe have a soft lining or not matters.

Yes, this works on square chimneys.