Turbo Groove automotive brake discs have a widened, arcuate slit that increases the flow of cool air, lowering the temperature of the brake pads and disc, while draining dust, dirt and hot gases better than a straight line, which can rust and become ineffective. Drilled holes remove surface gases when braking from high speed, while not weakening the structure of the disc as in through drilling. TECHNICAL DATA Type: Drilled and Slotted Full / Ventilated: Ventilated Number of holes: 5 Diameter (mm): 338 Height (mm): 73 Thickness (mm): 26 Minimum thickness (mm): 24 Axle application: Front APPLICATION Brand Model Engine Value Power (HP) Yearbook BMW 1 SERIES (E82 COUPE) 135 3.0 TURBO 302 2011-2013 BMW 1 SERIES (E82 COUPE) 135 3.0 TWIN TURBO 302 2007-2010 BMW 1 SERIES (E82 COUPE) 135 3.0 TWIN TURBO 302 2010-2011 BMW 1 SERIES (E88 CONVERTIBLE) 135 3.0 TURBO 302 2011-2014 BMW 1 SERIES (E88 CONVERTIBLE) 135 3.0 TWIN TURBO 302 2008-2010 BMW 1 SERIES (E88 CONVERTIBLE) 135 3.0 TWIN TURBO 302 2010-2011