This educational necklace "halti" was recommended to me by a dog trainer. My dog was pulling all the time ride with this material more real problem, and the system does not interfere with the dog, do not hurt him and did not hurt him. Ideal for a firm but gentle education !!! very strong and patented (beware of counterfeits, well take the "halti"). Watch simply that the animal does not attempt to remove the part with his dough around his muzzle and more that he does not nibble the collar (my dog managed the feat). The article is solid, in case of breakage do not worry since security is added to the collar "classic", the animal can therefore not escape. I absolutely recommend this effective product and is not an instrument of torture for our dear doggies !!!!!!!!!!