Yes that's me on track! Black Diamond rear brake discs drilled and grooved .Comes as a boxed pair left and right.
High-performance heat treated and phosphate coated disc easily outperforms and outlasts the stock disc.
My choice for road and competition work match up with Black Diamond pads for best all round performance.
I tested Green Stuff pads against the Black Diamond and the Green Stuff ones  glazed up and started to break up and rapidly faded!!