Please note: The literature that comes with this product states that there are 3 colors, which is incorrect. There are 2 colors -- Black and Yellow -- and it is recommended that you change the colors every 3 weeks to get maximum results. Otherwise the birds get used to the colors. Widely used in orchards, rowcrops, berries and grapes, these balloons have multi-colored stripes forming a scary bull's-eye, with a metallic dot in the center that flashes reflected sunlight. Hundreds of growers have reported reduced damage from blackbirds, starlings, cedar waxwings, woodpeckers and others. The control is not effective on single songbirds such as robins. Suspend the balloon(s) 2'-3' above the crop on individual poles or along a wire. No helium is required. Use 4-10/acre. These heavy duty balloons will last many seasons.