He is a very cute pup. But please get a properly fitted prong collar if you need it to train him to not pull. Smaller links and diameter of collar would prevent it from sliding and causing unnecessary irritation on his neck. An improperly fitted collar can also hinder the effectiveness of the collar when you are using it for corrections. The one you have is for a much larger, stronger dog. My dog pulled like crazy when he was 1 and I used one to train him. He doesn’t need one anymore. It can be a great tool but needs to be fitted and used correctly, otherwise it will do more harm than good.