Crunchers are hydraulic powered jaws, which can be placed on top of a wall of concrete or masonry, crushing and breaking as the jaws close.
The hand held cruncher can take down walls with reasonably less dust and vibration then other methods. Crunching does not require diamond holes to be pre-drilled and the resulting rubble is of much smaller dimensions.
As long as a free or open edge is accessible, the jaws are installed over the concrete to be removed. The jaws come together and the concrete is crushed and then removed. Re-enforced steel concrete can be cut by angle grinders as it becomes apparent.