GoToTags NFC Epoxy Key Tag 28 mm Circle - NXP NTAG203 - Blue - 10 Pack Includes 10 blue NFC key tags with the GoToTags NFC symbol on one side and the word NFC on the other 28 mm (1.10 in.) circular key tags with a black stretchy cord or double silver key ring attachment Waterproof PVC housing and shiny epoxy cover protect the NFC chip inside 137 usable bytes of data; suitable for a url, text, small contact record or single action phone trigger Compatible with all GoToTags software and NFC-enabled phones