it fits the bars in my gym -
Sometimes it's hard to squeeze them to fit them on, but at least they are secure and tight when on.
Simple mechanism, effective in securing discs. Had reason to replace one unit as it was too small
Seems to be coping with continuous use. Effective high tension on spring clips.
You need to have adequate strength in wrist and fingers to secure the clips.
Do the job Nothing
Suberb. Exactly what it says on the packet.