Factory filled with coolant, then sealed and pressure tested - requires | zero maintenance for years. | Highly optimized pump and water block guarantees the best water flow | and system performance. | Specially designed 120mm radiator provides superior heat dissipation | and fits in almost any case internally and externally. | 120mm JetFlo with a wide RPM range to fine tune and balance fan noise | and performance. | Blue LED indicator lights up when it is operating.