Answer from Formula:watti said:
B4 Sport is more economic than B4 Pro but is more or less the same model.
The B4 Sport caliper is anodized instead the B4 Pro caliper is painted
The B4 Sport bleeding screw is in plastic instead the B4 Pro bleeding screw
is in aluminium.
The B4 Sport has organic pads, the B4 Pro has sintered pads.
Best regards,
Formula srl