Your pet needs a reliable form of identification. Even if your pet wears a collar and ID tag, collars can break off and tags can become damaged and unreadable. Alternatively, a microchip is about the size and shape of a grain of rice and is placed underneath your pet's skin between the shoulder blades. Microchip implantation is a quick and harmless procedure. Each microchip is unique and carries vital information about your pet, including your name, address and contact information. When a microchip is implanted, the pet owner must register the microchip.