I have bought a few of each of these and I really like the way they work especially the bobbin clipper and the thing that holds the bobbin with the thread spool the peels are great but I have most of my threads in plastic cases so I don't have a huge tangle problem
even with this price discount these are expensive
I use mine for my away from home sewing so I use a set of (3) pieces the peel the bobbin clip and the joining piece for each thread so this set of 60
is really a grouping for 20 threads so that's over $2 per thread set
of course they are reusable and for my use 20 units are most likely enough for me