I give a gelcap to each of my 3 cats daily. I purchased a 5-10 lb. and a 10-15 lb. bag based on my cats' weight and fortunately both accommodate the cats perfectly. I put the open bag on a counter top and put the cat on it, fasten the neck velcro first, then zip up the back being careful not to catch fur. Sometimes they struggle and sometimes not, but either way both I and the kitty are safe. Getting them to swallow is another issue, but they are comfortably and safely contained until I let them out. The zipper is big and plastic, the bag is sturdy nylon. Great product! I haven't yet tried to trim nails because my husband (the cat whisperer in our family) does this job using a blanket and a muzzle (they can't see with the muzzle on), however I think the bag would work fine for this too. So too would rear access to the cat be pretty easy. If you have a feisty cat, do yourself a favor and get a restraint bag.
It's pretty much what I expected and I am happy they come in sizes. I need to do the back feet with claw covers and I can't do it with this because one can only expose the front paws.
The restraint bag has been very useful for the force-feeding and IV fluids. I had a bit of a problem determining the right size; the Vet loaned me an older model of this same item, labelled "Large" size. So, I ordered the 10-15 pound-cat bag, thinking this was the same. The newer, 10-15 pound bag was a bit larger (than the Vet's bag), but still works. Being larger, the cat can move within and may fall over. If the collar isn't tightly set, he'll slip a paw out through the collar. Easy problems to resolve; just be aware of these issues.
The bag is OKAY...not great for the price. It's a little big for 10lb cats, mine was able to get out of the (adjustable, but not enough)neck hole. The zipper is hard to get started, so I advise getting it started first. The bag doesn't have an access hole to give fluids and only 2 front paw access holes, no back ones.