Tinsnips are tools used to cut thin sheet metal. They use the same principles as common scissors, but are able to handle thicker and harder material. There are three different types of tinsnips; straight cutting, left cutting, and right cutting. Straight cutting in a straight line, left cutting snips (usually red) will cut in a curve to the left, and right cutting snips (usually green) will cut in a curve to the right.
In practical use the red snips
pictured will be used in the right hand, for straight or curving cuts,
with the base material to the right being cut neatly and the left hand
will be pulling away a spiraling offcut. The green snips work in the opposite fashion in the left hand, with the waste being on the right.
A similar tool called aviation snips can cut sheet metal with less effort than tinsnips.
A compound lever mechanism provides greater control with less effort.
The serrated jaws prevent slippage and withstand heavy use. Also it is
designed with a latch than holds the jaws closed if desired. The
insulated handles have the same color-coding as with tinsnips described above.
A tool called a hand notcher makes clean V-shaped cuts in
sheet metal without slippage. The compound-action handles produce
necessary leverage for fast cutting.