content: This is a great idea. I don't have to worry about stepping on my cat when I walk around the house with the lights off. Only problem is my cat has a med size neck (from other custom collars I've ordered)and this collar is very large. I had to move the black plastic buckle to the middle of the "plastic glow band" in order to fit my cat. The glow part is plastic and stiff, so the buckle doesn't easily adjust to fit smaller cats.