I agree with everyone else on the break-away cat collar. When he gets older and his neck is bigger, you might consider getting an embroidered ID collar. I could never hang tags from Bella's collar because she could chew the tags, even the metal ones
. Here is the collar that Bella uses now:
Personalized Dog Collars / Personalized Adjustable Dog Collar -- Orvis
If someone makes embroidered break-away collars, better yet! Here is a link to a company that embroiders all of their products, including break-away collars. Please note that the embroidery is charged separately from the collar, and you have to follow another link from this page:
The Cozy Critter - Safety Breakaway Collar