The Lisle Line Sockets, 17Mm & 21Mm - 12490 are the perfect addition to any toolbox. These high-quality sockets are designed to last and are made from durable materials that can handle the toughest jobs. The 17mm and 21mm sizes are perfect for loosening and tightening nuts, bolts, and other fasteners. The sockets feature a chrome finish for maximum corrosion resistance and a knurled grip for easy handling. They come in a convenient plastic storage case, so you can keep them organized and protected when not in use. Whether you're a professional mechanic or a DIY enthusiast, these sockets are sure to make any job easier.