Enermax T.B. Silence 120mm Ultra Quiet Twister Bearing Cooling Fan, Black UCTB12
This Enermax T.B.Silence 120mm fan is everything you need for your case fan need.  It comes with magnetic bearing technology call Twister Bearing to ensure durability with MTBF up to 100,000 Hour.  Carved Halo Frame, Batwing design increases airflow to maximize cooling.  Fan speed is set at 900 RPM with air flow of 42 CFM.