CSF Race-Spec water cooler for BMW E46 M3

CSF Race Radiator for BMW E46 M3 Triple Pass Radiator Featuring CSF's exclusive B-Tube technology and 6.5mm multi-fin fin height, 1-hour polished mirror finish, CNC-machined mounting bracketsTrue "drop-in-fit" with no modifications necessaryPart number : CSF # 7058 Fits: BMW E46 M3CSF manufactures the industry's most advanced and efficient radiator cores by utilizing innovative tube and fin technologies with industry-leading testing methods to maximize airflow and heat dissipation. These techniques allow CSF to stay one step ahead in radiator technology!"B-Tube" Technology - Unlike a regular "O" type oval radiant tube, CSF uses a specially designed "B" shaped tube. These "B-tubes" are carefully formed and then soldered over the seam to seal them. CSF is able to use thinner and lighter aluminum material (better cooling efficiency) because this design is actually stronger than regular "O" shape tubes which are welded. The construction (inlet in the middle of the tube which is seam brazed) increased the heat transfer surface of the tubes by about 15% compared to normal tubes. You get the efficiency of 2 smaller tubes versus 1 large tube with the same space criteria. With "B-hoses" you can get "Dual Liquid Laminar Flow".High Efficiency Multi Louvered Fin - CSF uses high-efficiency multi-louvered fins that are carefully and precisely aligned to maximize airflow through each cooler core. Fin specifications are carefully measured and calculated for each application and tested in our wind tunnel lab for maximum heat dissipation efficiency.