The first tool we purchased was the one to the left. It is a pill crusher, and a pill cutter. We still find the crusher portion very useful when breaking down "horse pills" as our veterinarian calls them, to fit the contents into gelatine capsules we purchase as well, (see below).
We found that the crusher/splitter was a bit difficult to use for splitting as one could not see through the splitter to ensure one was in the proper position, so we purchased a second splitter that made life very easy.
Another very useful item that comes along with these gadgets is the gelatine capsule, and, when you manage to reduce the size of the pills, you can create very small capsules that are easily swallowed at the most difficult of times, as we found with Max when his throat was being squeezed by the cancer tumor. He still managed to swallow the #4 size capsule we purchase.
This is the greatest invention for housebound felines, and it is amazing how many uses they find for it over time, aside from getting out aggressions. It can also make a great cat version of a teddy bear to hug while sleeping, or as a pillow. It doesn't matter how old and tired these bags get, the cats have trouble with the letting go process once one has been identified as their specific possession.
This is something I avoided using, and we had it sitting around "just in case" it was every needed. When we took in Thumper, he was terrified of having his nails clipped, however, I broke down and used the muzzle as he was 'brawling' with the other boys and causing tears in their skin, which was not good and something had to change. After a few sessions with the muzzle on, Thumper settled down to the point that I could attempt to do his nails without the muzzle, and now he is just fine, and the other cats are free of scratch wounds. In a multi cat household, I would now never be without a muzzle in my arsenal. The specific muzzle we use is made of nylon and covers the eyes.......most important feature.
We have had several felines who have gradually been trained to be 'harness friendly' as the dangers far outweigh our boys' need for fresh air, particularly in our new home.
In the past, we have tried everything we could find locally, and ended up purchasing a harness meant for small dogs. Marmaduke used to love to have the harness put on for evening walks, and it was stress free for all of us to be able to give our cats some fresh air time when they wanted it, without fear of losing them. One time, Hamlet and I were outside after dark and we walked around the corner of a building right into the path of a coyote. Without the harness, we would definitely have lost him.
A word of warning here in that Legolas learned how to press against the pavement to hold the harness still while he put his front paws above his head and slid out of this well made harness, so we have yet to find the Purrfect harness that will allow him time outdoors.