1) Hand tool 2) Street noisemaker 
[fabrication] An air hammer, also known as an air chisel, is a pneumatic hand tool used to carve in stone, and to break or cut metal objects apart. It is designed to accept different tools depending on the required function. ==Function== ==Tools== The following are various tools that can be used in the air hammer: ==Free-standing style== Fr...
A pneumatic tool that uses pressurized air to drive a hammer head back and forth several thousand times a second. Air hammers come in a wide variety of sizes from handheld devices no bigger than a blow drier to five-foot-tall forging hammers for use in blacksmith shops and welding plants. Pneumatic ...
[n] - a hammer driven by compressed air
jackhammer noun a hammer driven by compressed air
a pneumatic hammer, usually portable.