A system for adjusting the height of a boom on a pipe handling apparatus. A cavity is formed in the base between proximal and distal ends. The boom is nestable in said cavity and has a distal end guided along the base. A pivoting member is pivotally coupled to said boom for raising a proximal end for positioned adjacent a work floor for handling of pipe therebetween. A plurality of ports are arranged along the boom at a pre-determined spacing. A plurality of ports are is similarly arranged along the same predetermined spacing along the pivoting member. The spacing of the boom and arm ports is such that a hinge pin can engage any one of corresponding pairs of boom and arm port when the boom is lowered to nestle inside the cavity as each boom port corresponds with an arm port.