... mount, easy, reliable; 3. swift from a excavator to a rock/concrete breaker Bolev Hydraulics:Bolev welcomes your ... used for convert a excavator into a rock/concrete breaker. it works as:3 ports, P port in, A port out, T ... port return line;position 1, P port to T port, ... line, breaker does not work;Position 2, P port to A port, breaker valve starts to work;easy ...