Fine brass type alloy wire OB-7S wire -This type has the smallest wire diameter in the series. -It uses a brass type special alloy, realizing a reduction of cost compared to expensive tungsten wire. -It exhibits maximum EDM performance in a wire EDM machine intended exclusively for using fine wire for precision machining of molds for lead frames, and so on. -The wire diameter is 0.07mmf. -Compared to 0.05mmf tungsten wire, the cut face is at least as good and also the machining speed is the same.