Cat lovers: Which is the best collar for a houdini cat?

Our cat has gotten out of yet another collar. It concerns me greatly because he is always trying to get outside, he has no front claws, and I’m concerned about something happening to him if he gets away.
We had a great one for him for a while, but I can’t even locate it since he has taken it off.
Does anyone have any advice on a great collar? He is a rather thin cat, and we’ve tried different brands, we haven’t tried a harness yet so I was also wondering if that is good for cats.

I would like it to be easily accessible, like from Petsmart or Petco. Something I can get rather quickly.