Flare-nut wrenches (or the crow’s foot spanner, according to the British) are commonly used wrenches which have set sockets on either side of the bar. They are mainly used to grasp nuts or bolts on tubes or other structures. The sockets grip the nut or bolt with just enough torque to prevent it from turning in the future. These are widely used by plumbers, because the jaws on the tool are thick and strong.
These specific wrenches are an excellent item to have handy in any car or other vehicle. The inside of the sockets are six sided, so their function is to grip nuts that contain six nuts without destroying it. These wrenches are ideal for tightening the nuts on temperature sensors, brake lines, and fuel hoses.
These wrenches are readily available for purchase from local hardware or online stores.
They are all usually made of steel, hence their strong capabilities. They are generally small sized, about 10 inches overall length, because their function is normally getting into the nuts or bolts of small crevices. Flare-nut wrenches can be found on online stores like Amazon, E-Bay, or Grainger (a site known for selling wrenches and other handy tools).
Flare-nut wrenches usually sell in sets with other wrenches of the same type. A set of six of these wrenches, all different sizes, goes for about $16 on Amazon. Some brands to keep in mind when shopping for them are: Tekton, Craftsman, Proto, and Blackhawk. Blackhawk manufactures a four piece set of the wrenches, ranging from 10 to 21 mm, for about $40. For a more extensive amount of these wrenches, Proto produces a 12 point set of seven wrenches ranging from 3/8 to ¾ of an inch for about $120.
Flare-nut wrenches are one of the most common wrenches used today, either by professionals or homeowners. They are more often used for plumbing issues and delicate car repair.