Leather holding tools are used to hold leather while it is being worked. For example, one might want to use pliers to hold a leather piece while burnishing it, or applying edge paint. They might be helpful to hold things while stitching, or making a specialized cut. Others hold glued leather pieces securely in place while the leather glue dries. While not primary leather working tools, tools that hold leather can be helpful every now and then for various needs.
It’s important to remember that any clamp or pliers that come into contact with the leather should have a soft surface on which it contacts the leather. In not, the leather could get deformed, cut, or marred by uneven surfaces on the clamp/pliers. Some clamp/plier jaws are coated with leather, making them perfect for leather on leather contact during holding activities.