The Quasar Science QSRB Ossium Rotator is sold separately in the Ossium Mounting System, which acts as a mini-grip head, giving you the most flexibility in positioning your lights or batteries. Screw directly to the Rail, Slider, or even the Battery Plate, allowing you to attach your batteries to any 5/8 or 3/8 Inch rod. Screw two Rotator Blocks back to back, giving you two swivel points on two separate axes.