The CRAFTSMAN 3/8-in drive spark plug socket is high quality and versatile. While you can spend less money for spark plugs in this size range, you don't want to skimp on quality just to save a few bucks. From servicing lawn mowers to weed whackers to vehicles, this spark plug set covers all of your bases. Once you have these tools in your supply box, you'll find yourself using them so frequently that you won't know what you did without them. The CRAFTSMAN spark plug socket set features the following sizes: 5/8-in, 13/16-in, 3/4-in and 18mm. Each one has 6 contact points. The spark plugs have easy to read markings, which is ideal for working in low lit and greasy environments. You will never have trouble finding the size that you need when you need it.