A sawzall is a powered reciprocating saw originally created by Milwaukee Tool company, but has become ubiquitous in the field. They are large hand tools, best operated with both hands. Sawzalls vibrate a ton, bounce around when they start a cut and have lots of disadvantages. But you find them everywhere for a simple reason: flexibility. With a sawzall you can cut almost anything this side of a tree, and you could use one to trim most trees.

Sawzalls have a pistol grip and cylindrical center body which includes the electric motor, which can draw as much as 11 amperes for a commercial product. They weigh around ten pounds (five kilos) and are easily controlled with two hands. At the far end is an rotating flat plate used to brace against the object to be cut. It has an opening in the center, through which passes the blade which is attached to a chuck.

It's the blades that make the sawzall. They can be short or up to a foot long. They can use very fine teeth for cutting steel or course teeth for ripping wood. It's hard to get a really straight cut using one. They aren't the tool to use if you need true precision but you can cut tree limbs or an opening for a sink in a counter top. You can cut unistrut and conduit easily, provided the object to be cut is securely held.

To sum up a sawzall is a large saw that doesn't do anything really well but will do almost anything. Sawzalls aren't so good as a band saw for cutting pipe, a jig saw for fine work, or a circular saw for ripping, but it will do the job. As tools are something that needs to be carried, a flexible tool is highly prized. Which is why almost every contractor no matter what the trade will have one around. Most journeymen own their own (including me). Which is why everyone makes one.

The term sawzall is a trademark of Milwaukee tool company, though the patent has long expired. If you see one in the field, no matter who made it, it's called a sawzall.