The Mule Knot (a.k.a releasable knot) is ideal to lock off the rope on the belay plate. There are many occasions in climbing when, belaying from the harness using a device which does not self-arrest ...
Mammut recommends use of the Smart HMS for the Smart 2.0. It is suitable for rope diameters from 8.7 to 10.5 mm. Add-on for the Smart 2.0 belay device to prevent the consequences of beginner’s errors.