These are some of my favourite weapons in the system and the forms are difficult in having jumping and rolling techniques. The knives themselves are much like the ones commonly seen in Wing Chun, but the guard is a rolled bar not square which makes it easier to reverse the knives.
There are two forms to be learned the first is relatively easy jumping and blocking in four direction performing the cutting as well. The second is more difficult in that it has rolling techniques as well has jumping techniques.
This is a very flexible weapon and because of the length can change height and direction quickly enabling the practitioner to defend against multiple opponents.
Within the system there is also a two man set involving the knives against the pole. Myself and John Farrell performed this many times, it is a very fast set and the pole is used double ended which is a real test of speed to defend and counter against.
The Baat Charm Dao can also be called mother and son knives and that is their traditional name within Hung Gar, but for us they were 8 Cutting Knives.