The DMM Belay Master Clip is an innovative, clip-on attachment that stops your belay device from shifting and cross-loading your locking carabiner. For added safety, DMM designed the Belay Master to not close unless the carabiner"s screwgate is locked. Product FeaturesMaterial: Auto Locking: Rope Diameter: Strength: Weight: 3.3 ozRecommended Use: belayingManufacturer Warranty: 1 year