Just bought a Craftsman 10" adjustable wrench . These are new to me I don`t remember seeing them around before. They are an adjustable Crescent wrench with a locking mechanism like a vise-grip plier. I have a adjustable wrench that I rarely ever used. Reason is with them even a good one you have that play in the jaws so you don`t get a good tight fit on the bolt and could slip or round off a nut.With these you close them in on the nut and then lock the handle grip and they form a tight bond to the nut. Same with a vise-grip if you were to use it on a nut that was real tight those aggressive jaws could round off the nut. This is a great idea in a tool and I picked it up at Kmart for $19.99 regular $39.99. They have a real nice rubberized handle too .