The first one I ordered the heaters were too short. Serves me right for going by a picture. The part number for the smaller version ends in 442. The larger one (No doubt for a 25 Cu.Ft refrigerator) ends in 443. It pays to measure and check sizes. I first replaced the defrost timer which is what usually fails. When the timer didn't fix the defrost I found it was the heaters that were defective. Replacement on my GE refrigerator was easy. First, turn the cold control to OFF. Don't disconnect the wall plug as you will want the freezer light to be working. After removing the shelves and drawers in the freezer, five Phillips screws remove the rear panel. You will probably find the cooling coils heavily iced. I put a small electric heater on the freezer floor and closed the door. Thirty minutes later the ice was gone but the drain pan underneath was overflowing. What a mess! Notice how the heater wires are dressed so you can dress the new wires the same way lest they get pinched behind the panel. Remove the two screws holding each heater and unplug the connector. Install the replacement heaters and dress the wires exactly like the originals were. Plug in the connector making sure the wires are not in contact with the light bulb. Make sure the edge seals are on the panel correctly and install the panel, the shelves and the drawers and turn the cold control back to it's usual setting. Buying the defrost heaters and timer from Amazon saved me more then $100.00 over prices at our local parts supplier. By installing the parts myself I figure I saved $200.00 over paying for a service call. Give it a try. All you really need is a Phillips screw driver and you can't really make it any worse.