Easement specialty equipment, parts and accessories for the utility industry, namely, digger derricks, power-operated, articulating, telescopic insulated lifts for use in landscaping applications, material handling machines in the nature of articulated telescopic booms incorporating removable load carrier jibs used to position loads within difficult to reach areas, and track-driven auxiliary power supply units therefor; Mobile cranes in the nature of digger derricks; proportional hydraulic-controlled machines, namely, truck cranes; All terrain tracked hydraulic drilling rig; Mobile cranes in the nature of digger derrick machines equipped with sensors for controlling, monitoring and switching hydraulic systems; digger derrick-type, truck-mounted drilling rigs; Fixed and mobile cranes in the nature of hinged derrick assemblies comprised of an upper derrick structure, a lower derrick structure, a hinge connecting the upper derrick structure to the lower derrick structure, and at least one hydraulic cylinder allowing the assembly to fold at the hinge.