The basic Argus with its cantilevered jib was general purpose yard pick and carry workhorse. The cantilever jib meant the height profile could be kept low and there were no exposed cables to get caught up in anything while working inside warehouses. It could be supplied with or without the wheel arch covers. Image 5. shows the basic chassis, Image 6 the electrical circuit breakers accessible from outside the unit and Image 7 shows the drivers cab with the crane control levers shown just below the steering wheel.

The basic layout of the power units are shown on the layout above 8. Shown Yellow is the Power Unit with a petrol or diesel engine coupled to an electrical generator. This can be seen through the side of the cranes in photo 9 above. The Slew motion is shown in Blue an electrical motor coupled to a gearbox driving a gear below the slew plate and engaging into the inside flange of the Slew Ring fixed to the chassis below. The Deric motion rising the jib shown green is a motor driving a small winding drum. The Hoist Cable shown Red is a similar but larger drum. The slew, hoist and jib motors can be seen in image 10 below. All the motions are controlled by three simple lever handles on the dashboard in front of the driver photo 11 below.

Access to all the driving gear can be made through removable panels on the sides of the housing unit.

Coles patent full/ automatic Reversing Steering Mechanism (image 12) allows control of the travel motion by normal directional steering wheel movement, regardless of the position of the superstructure relative to the chassis. The operator is thus relieved of the necessity to ascertain whether the jib is over the front or rear of the chassis when steering. The steering is operated through a reversing box to a bearing which transmits the motion from the superstructure to a steering worm box coupled to the front axle drag arm by an automotive type link.

The Coles Steering Reverse Box is situated at the base of the steering column. All gears are accurately machined from high carbon steel to provide maximum efficiency and long life. The motion is transmitted from the box by means of an adjustable chain drive. As the crane is slewed over the rear of the chassis a rocker arm contacts a ramp situated around the slew bearing rim. (coloured green on drawing) This alters the position of the rocker arm which in turn changes gears inside the reverse box to correct the direction of rotation of the steering motion.

Coles self-propelled Crane Chassis were engineered for the job and were strong ridged units of deep section side members, stressed and braced for maximum strength and rigidity. The rear axle had fully floating axle shafts and differential with spur and spiral bevel reduction. Conventional laminated springs are used for the front axle. The slew ring was centred to make the weight distribution even on all tires situating its centre closer to the double none steering wheels at the rear. Powerful foot operated, twin leading shoe air or hydraulic brakes act on all four wheels and a hand parking break acts on the rear wheels only.
The Coles self-propelled crane chassis was driven by a powerful electric motor on either the rear only or all four wheels. This motor was powered by the generator on the crane superstructure, power being taken down through the centre of the rotation axes pin.