RENNtech ECU Hand Held Tuner (HHT) for CL 500 | C215 | 320 HP / 355 LB-FT | MY2001-2006RENNtech ECU HHT (HandHeldTuner) for the 215 CL 500. Up to 320HP and 355 LB FT. Gains: +18HP & +16 LB FT. RENNtech HHT (hand held tuner) allows you the unlimited ability to switch between tuned and stock ECU programming and requires no ECU removal! Our proprietary tuning module stores both the RENNtech tuned file and your vehicles stock file. The module plugs directly into the OBD2 port and delivers the file you choose directly to the ECU. Programming