You can often use a single adjustable wrench, often called a Crescent wrench, in place of a whole set of wrenches. This is easier than finding the right wrench to fit, and works anytime you have enough room around the fastener. However, when you need to apply a lot of force, it is better to use a six-sided socket or a box-end wrench, because an adjustable wrench can round off the fastener’s sides. To use an adjustable wrench properly, loosen its jaw enough to apply the wrench quickly, then turn the thumbscrew to tighten the jaw before turning. The force of the turn should be against the back, solid jaw. If not, flip the wrench over. In the case of a small adjustable wrench, you can leave your thumb on the thumbwheel. With a bit of practice, you can smoothly open the jaws a bit as you place the wrench, and turn the thumbwheel the other way to tighten the wrench just before turning, to make using the wrench fast and secure.