You can use the removers on pets like dogs and cats. The mechanical principle of sliding the tool under the tick and lifting it out applies regardless of whether the skin is human or animal. The two sizes are helpful here as well; a larger remover might be better for an engorged tick on a dog's back, while the smaller one could be needed for a tiny tick nestled in a cat's ear fur.
When dealing with pets, ensure you have good visibility by parting the fur. Try to keep your pet calm and still during the process. After removal, check the bite area to confirm nothing is left behind, and monitor the spot for a few days for any signs of excessive redness, swelling, or irritation. If you have concerns about the tick's attachment duration or your pet's reaction, consult your veterinarian.