GPS chip implants are tiny microchips that are implanted into pets in order to help locate them should they go missing. They are the size of a grain of rice and implanted under the skin between the shoulders by a veterinarian.
Each GPS chip implants contain identification numbers unique to each pet. Once activated through a service provider, contact information is linked to the identification numbers. Most animal shelters, rescue organizations and veterinarians possess scanners that can read GPS chip implants.
GPS collars are an alternative to GPS chip implants. Human GPS microchips are in development but are not currently available.