The Klein Tools adjustable wrench is designed with smaller size but the ability to handle heavy-duty jobs. This wrench is manufactured from heat-treated alloy steel for strength and has a high polish chrome finish. It also features a lightweight 12-inch design with an extra-capacity jaw. For more than 160 years, Klein Tools has manufactured premium-quality, professional-grade hand tools that deliver the performance, durability and precision needed to get the job done right. Our family of engineers, workers and craftsman continue to put six generations of expertise into every tool we create by using only the highest quality materials, superior workmanship, and keeping manufacturing as close to home as we can. Klein isn't just the name of our company, it's also our family name. And since we're an American company that's family-owned and family-run, you know you can count on us to be here tomorrow. Klein Tools doesn't just make great products, we make great products that stand up to the demands of the professionals who use them every day ... Since 1857. Klein D507-12 12-Inch Adjustable Wrench-Extra Capacity. The Klein D507-12 12-Inch Adjustable Wrench-Extra Capacity has extra capacity that allows use of a smaller size wrench to handle bigger jobs, especially in confined spaces. The Klein D507-12 12-Inch Adjustable Wrench-Extra Capacity is forged heat-treated alloy steel for maximum strength and light weight. The Klein D507-12 12-Inch Adjustable Wrench-Extra Capacity has a high polish chrome finish.