• Three braking positions• Two supplementary braking spurs allow friction to be varied during descent• Stays securely attached to the harness during rope insertion• For single ropes between 8 and 13 mm in diameter• Used with a carabiner with a cross-section of 12 mm (e.g. WILLIAM), it creates a «rigid» carabiner / descender unit and maintains noise discipline The descender is used with rapid technique and can not be dropped.