Great buy! Very effective, very calm nature of My dog, little spending hours bark when we are not at home, so we put the necklace in case of absence from us. He quickly realized he took two landfills and no longer barked, now we just put the collar him (in off mode) for its disuasif side! And it works. Really happy with our purchase. Before that the collar does not work (cétait the case for my husband, make sure it is turned on!)