The design allows the disc to cool faster and prevents fading on long downhill breaking. The disc is made of chromium molybdenum alloy steel.
This results in better feel with better braking.
All discs have the same outside diameter as the OEM.
Motomasters brake discs have MX1-MX2-SMX is used by the "World Champions" during 2010-2011-2012-2013-2014.
They even won the US Nationals in 2014 with Ken Roczen!
Moto-Master discs and pads are used in;
KTM USA, Ken Roczen, Ryan Dungey, KTM RedBull, Marvin Musquin, Antonio Cairoli, Ken Dijicker, Jeffrey Herlings, Jordi Tixier, Husqvarna Factory, Tyla Rattray, amongst others.