Feature:1. Readable Key Fobs: Access control keychains are read only, not rewritable, you cannot reprogram them, with high precise and reliability.2. High Sensitivity: Access control tags use smart chips, thick and high quality copper wires, and sensitive induction.3. Unique Numbering: Each key fob has been preset with a unique number, this 10 digit number is engraved on the label casing.4. Wide Application: Applicable to residential access control, apartments, hotels, hospitals, schools, elevators, buses, subways.5. Durable Material: The readable key fobs shell is made of high quality ABS material, which is lightweight, shock resistant and drop resistant.Specification:Item Type: Door Entry Key FobsMaterial: ABS, copperApplication: Keychain used in access control systemWorking Distance: Approx. 0-10cm/0-3.94inOperating Temperature: -25C + 75CStorage Temperature: -15C + 45CMultiple Visits: YesAnti Interference: Yes.Package List:100 xDoor Entry Key FobNote:Do not place the product in an excessively corrosive, humid and high temperature environment!