If you plan on bleeding or fixing your radiator, you’ll need a radiator key. The only problem is finding one, because not all stores carry them. To buy a radiator key, you need to check out local hardware stores or look online.
Visit smaller, independent hardware stores, especially those in an older area of town. These stores often carry parts and pieces that you can’t find in the larger chain stores. If they have the keys available, you can usually get them for a much smaller amount than you would elsewhere.
Check at larger hardware stores like Home Depot or Lowe’s. These stores don’t always carry radiator keys in stock, but they can usually special order them when a customer asks. You should ask the manager about their stock.
Look at ACE Hardware. Most of these stores are now owned independently instead of by the company, and they usually carry radiator keys. The one thing you should know is that the radiator keys they sell are usually more expensive than other stores.
Bid on radiator keys from eBay. Sellers on this site offer just about anything you can imagine and that includes these keys. When you bid you should check on the feedback of the seller and factor in the shipping costs to your location.
Buy your radiator key directly from the Great Hardware Store website. This store carries radiator keys in stock, and their prices are really reasonable (see Resources below). Before you commit to buy, though, find out if you can get one from a hardware store in town so you can avoid paying shipping costs.