The present invention provides a boom system 1 for breaking and manoeuvring oversize material. The boom system 1 is mounted or attached to a vehicle. The boom system 1 comprises a base 2, a column 5 protruding upwardly from the base 2 and a boom arm 3 moveably connectable to the upright column 5 at connection point 16. A moving arrangement 4 is provided to move all or part of the upright column 5 towards and away from the base 2 so that the connection 16 between the boom arm 3 and the upright column is moveable towards and away from the base 2. A mobile crusher comprising a boom system 1 for breaking and manoeuvring oversize material is also provided.