The present invention is directed to a coordinating catalyst system comprising at least one metallocene or constrained geometry pre-catalyst transition metal compound, zirconium dichloride), at least one support-activator, and optionally at least one organometallic compound, in controlled amounts, and methods for preparing the same. The balancing device includes a stationary support structure including an overhead support and a plurality of upright supports, and a suspended platform hanging from the overhead support by first and second suspending members. Further, when the heating mode is set and the detected temperature of the printhead is lower than a second heating threshold temperature, a heating unit heats the printhead. The storage switches couple to the assistant unit.