If your windcups have stopped spinning in your weathervane system, then our replacement sealed ball bearings makes this a very easy fix. These bearings are for our own brand of rain gauge garden stake weathervanes and may not work in other brands. To install the new bearing, disassemble your weathervane system and hold the windcups and gently tap the center to remove the non-working bearing, then you can easily push a new bearing back into the same location and it will spin again and again. We include an extra bearing so you will have one for the future if it might be needed. Our price includes shipping.