This is a rounded-end steel finishing trowel, used to smooth and finish fresh concrete.
For stamped concrete, it helps to:
* Work broadcast colour hardener into the surface after it absorbs moisture.
* Flatten small ridges and close surface marks before stamping.
* Produce an even surface ready to receive the stamp pattern.
Its rounded ends reduce drag marks and prevent the corners from digging into the concrete. Avoid excessive trowelling, which can bring too much paste to the surface.