The lightest breeze will make them spin. Cleverly made by having many strips of wood threaded onto a central axis and then decorated. They are painted with the design on both sides and are extremely effective. They are delivered flat (as seen in one of the pictures) and you simply 'twist' them, one section at a time into the desired shape. I have shown two ways of doing this one with a full double helix and one with a single helix. You can vary the effect depending on how far you open up each section. Please check the dimensions given carefully to access if this product is the correct size required.