Feature: 1. Protect your key fob from duplication and auto \"relay hack\". 2. Easy to carry out with Keyring hook and minisized. 3. Comes with Two layers of high-shielding fabric on all sides with a protective ballistic nylon water-resistant outer shell. 4. Block Car key FOB Signal: Keep your car\u0027s security system from getting hacked. 5. Compatible Size: 12.8cm(5inch)x8.3cm(3.3inch); Fits for Car key FOB, Driver License and More. 6. Protect your key fob from duplication and auto relay hack; Easy to carry out with Keyring hook and minisized. 7. Protect your key fob from duplication and auto relay hack. 8. Protect your key fob from duplication and auto relay hack; Specification: Block Key Fob RFID Signal: Prevent unwanted signal communications and signal amplification attacks to your keyless entry system. Features: Protect your key fob from duplication and auto "relay hack"; Easy to carry out with Keyring hook and minisized. Comes with Two layers of high-shielding fabric on all sides with a protective ballistic nylon water-resistant outer shell. Block Car key FOB Signal: Keep your car's security system from getting hacked. Compatible Size: 12.8cm(5inch)x8.3cm(3.3inch); Fits for Car key FOB, Driver License and More. Warm Reminder: 1. Do Not Bleach/Dry Clean/Warm Iron/Hand Washing Excessively, or it will destroy the nano layer and affect the effect of use. 2. The outer layer is just radiation,The inner layer is the shielding signal. 3. Signal Shielding bag must be closed, or it will affect the effect of use. Package Content: 1 x RFID Blocking Bag with Keyring Package List: 1 x RFID Blocking Bag with Keyring