I'm selling this because the size didn't fit. I only put it on my dog's neck once. This is a full choke collar, used for training and discipline. Generally, it's said that a length about 5-10cm longer than the dog's neck circumference is ideal. When putting it on, it should slide over the head easily, and when taking it off, it should be snug enough that you have to remove it by taking one ear out at a time.