I have got this HS prong collar 2,25 mm for my 4,5 y.o. American Staffordshire Terrier walking. She is with me for several weeks and she requires patience and efforts to walk on a leash. I used a choker collar at once, but it was too weak for her power. She also needs socialization, that's why she has some problems with other dogs in walking. Then I decided to get a prong collar with you, for the price here is more reasonable than at other stores. Also I like that I can get extra links here at once. I've received it within 6 days. The prong collar has a great benefit. My dog obeys and comes up to me. I can distract her easily when we come to other dogs. I think now we may handle her much easier with the help of the prong collar and she becomes more confident in walking. I recommend it.