I bought this for my small chihuahua because she slips out of every other type of collar or harness. She has a slim head like a greyhound not a "apple" shaped head. She is in between sizes for the harness sizes & they are all either too small or a little too big which means she can slip out of the harness. She slipped out of her harness the last time in the vet parking lot which is right off a major busy highway. This collar is perfect. It is a small width suitable for her small neck. It is fairly soft so it is comfortable for her to wear. She cannot slip out of this collar at all. When it starts to tighten up, she will immediately stop pulling. I was so happy to find this type of collar on Amazon. I was unable to find one at all locally in the stores. All of the collars were either all chain or with the section that tightens made with chain. They were also not small enough. I had bought one like this collar years ago for my other chihuahua (it also was the only collar that worked for my other dog) at a local pet store, but they no longer sold these collars. I also like the bright pink color.