A settling basin of a wastewater treatment system, the settling basin comprises a collector chain for driving a plurality of flights through the settling basin, the collector chain including chain links comprising a plurality of side bars including a plurality of inner pairs of side bars and a plurality of outer pairs of side bars, and connecting pins configured to join the plurality of side bars, each connecting pin including a first end and a second end on an opposite end of the connecting pin from the first end, and flanged rollers disposed on the connecting pins between the first ends and second ends.