Description from the vendor website:

Fuel your dog’s training sessions with ¼ inch of pure protein. These single-ingredient, North American freeze-dried Pork Hearts contain essential B vitamins, zinc, and iron, which keep your whole dog healthy and happy. Each bite-sized morsel is only 1 calorie, making them ideal for the repetitive rewards required during training. Whether you're working on “sit” and “stay” or teaching new tricks, these delicious, crunchy Mini Trainers are sure to motivate your pup to learn and grow.