LIGHTWEIGHT & WATERPROOF: These NFC gadgets are thin and compact so you can carry them easily as alternative key or backup key... if you do not wish to use smartphone to unlock. USER SELF-PROGRAMMABLE via eGeeTouch Manager App. Easily set it by your own. When a fob get lost, simply delete it from app. Deleted Fobs are no longer be able to use by someone else once found Follow the Instruction (Youtube video available) on HOW to get to the NFC MODE of operation (Default MODE is for Smartphone to access lock). Consumer version FREE app may program up to 20 fobs for accessing each padlock. COMPATIBLE with ALL eGeeTouch Smart Locks, Smart Padlock, Luggage Locks and Travel Locks FOR COMMERCIAL, SCHOOL and GOVERNMENT APPLICATIONS: use of large numbers of up to 300 fobs/tags assigned to many users for accessing a SINGLE padlock, an Commercial paid App is required and an Intelligent Access Management Software is also available to empower administrator(s) to assign, revoke, track large number of users, please contact our Sales Support at: www.egeetouch.com/contact/sales-enquiry for further details., Manufacturer: JSB Tech