Opteka CBW-2 Counterbalance Weight for the Opteka CXS-300 & Other Shoulder Rigs with 15mm Rods Weight: 4.6 lbs (2.1KG) Compatibility: Opteka CXS-300 and other shoulder rigs with 15mm rods May be stacked with the CBW-1 (sold separately; Search for: B005S1D4J0) to achieve the desired balance 1 Year Warranty