PetSafe® Stubborn Dog Add A Dog® Extra Receiver Collar Collections_Australian Made It’s a breakthrough nutrition that It’s a breakthrough nutrition that supports each cat’s unique gut microbiome for healthy digestion and balanced nutrition that helps your cat feel their best the Seresto dog collar is the simple This PetSafe® Stubborn Dog In Ground Fence extra receiver collar can be used to add another dog to your PetSafe® In Ground Fence system or as a replacement collar (not compatible with the UltraSmart® and YardMax® systems) The collar features 4 levels of static stimulation at a higher intensity especially for stubborn or hard to train dogs