This is one of the best hoop attachments available, and it has enough strength to pinch a weaker hoop when you tighten it too much, so use it with care.
It will take the thinnest diameter of rods up to 12mm. max.
Most Tama rod clamps go up to 12mm, which is a factor if you want to clamp 12,7mm's (such as Gibraltar's): those won't go.
It's heavy, it feels bomproof, and knowing Tama: it is.