Some customer reviews have reported that their puppy has been able to penetrate the cloth however we believe this is because puppies have very sharp needle like teeth when they are young. (doggytoggery.com)
Puppies have sharp needle like teeth which can easily hurt very young children when playing. (homealabrador.net)
«We are using sharp needles at a high temperature, when the plastic is molten,» explains John Hughes, the inventor of the fingerprinting system. (newscientist.com)