The piston rides in a cylinder and creates air ... small areas of concrete and chisel tile. Over $225 Rotary hammers in this price range deliver an impact energy of over 10 ft.-lbs. and can drill ...

In a rotary hammer, a cylinder of air is compressed by a piston, which in turn beats the bit. In a hammer drill, two ribbed ... that the model I have is on the small side for rotary hammers.

Using a simple dial, you can choose between the three operating modes—pure hammer, rotary drill and hammer, or pure drill—which are all strong enough to break through tough concrete.

Rotary air motors aren't new, as any mechanic wielding pneumatic tools can tell you ... configuration allows the air engine to be very small and compact, yet very powerful.

However (and here’s a bit of a spoiler alert), if you plan on getting a lot of use out of your rotary tool, the corded Dremel 4300 is still the best. Cut the occasional small bolt, drill small ...