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: 200mmI.D: 86mmMinimum Thickness: 3mmDisc Position: Front Left or Right Fits: Yamaha YFM350A BRUIN (Auto) 2WD 2004-2006 YFM350A GRIZZLY 2WD 2009-2021 YFM350AG GRIZZLY 2WD 2018 YFM350FA BRUIN (Auto) 4WD 2004-2006 YFM350FA GRIZZLY 4WD 2007-2021 YFM400 KODIAK 2003-2006 YFM400FA GRIZZLY (AUTO) 4WD 2007-2008 YFM400FW BIG BEAR (SEMI AUTO) 4WD 2007-2013 YFM450 Kodiak 2003-2006 YFM450FA GRIZZLY AUTO 4WD 2007-2016 YFM450FAP GRIZZLY EPS AUTO 4WD 2013-2018 YFM450FAP GRIZZLY EPS AUTO 4X4 2011-2012