To help manage your strong-willed pal, the PetSafe Stubborn Dog In-Ground Fence Containment System comes equipped with five adjustable levels of correction, including a tone-only plus vibration mode. The adjustable collar is especially designed for hard-to-train dogs. Relax, help is on the way! Four adjustable static correction levels plus tone with vibration only mode. Ideal for training hearing-impaired dogs. Waterproof receiver with low-battery indicator. Works with multiple pets (additional receiver collars required).