MTX solid discs are constructed using one complete segment of Japanese SUS 420 stainless steel then heat-treated to HRC 36+-2. Lightening and drill hole patterns are as per OEM designs to improve braking performance and reduce the temperature of the disc.MTX Discs provide amazing braking control for your motorcycle. All MTX discs are designed and manufactured with world-leading cutting edge technologies:Precision CNC machined and laser-cut technologyJapanese SUS 420 Stainless SteelReplacement for Original EquipmentOEM Design; lightening & drill hole patternsSpecifications:O.D: 240mmI.D: 121mmMinimum Thickness: 3.5mmDisc Position: Rear Fits: Honda CR125R 2002-2004 2006 CR250R 2002-2007 CRF250R 2004 2008-2013 2015-2019 CRF250X 2004-2007 2009-2016 CRF450R 2002-2006 2008-2009 2011-2012 2014-2019 CRF450RX 2017-2020 CRF450X 2005-2016