Sevenfriday watchheavy duty box authenticationthe hdb is equipped with a nfc chip located on the inner sponge which allows its owner to authenticate the heavy duty box via the sevenfriday mobile application you can scan the hdb with a nfc enabled mobile phone to confirm its authenticity the app will confirm immediately with the chipped models you can be assured you are not buying a fake registrationowners of a chipped sevenfriday can register their hdb via the sevenfriday mobile app