They mean Acceleration Slip Regulation (ASR). This system can apply rear brake pressure to limit wheel spin. I don't know why a particular friction material would not be suitable unless it has poor fade resistance.

I've been using Repco Deluxe and Deluxe Plus on my 201 since it was one year old... a little more pedal effort is required, but very little dust, easy on the rotors, quiet, and long life.

The OE pads worked well, but dusted horribly, squealed, tough on the rotors, and had short life.

If whoever markets those pads can't even properly name ASR, you should use something else.

Duke