Information of Opastry Faraday Bags with Strap - Purse Strap: 25.6-49.2 IN - Faraday Bags for Phones: 7.87 X 5.5 IN - Material: Non-itchy Silicone Coated Fiberglass & Super Shielding metallic fiber Signal Blocking Function -Inner shielding material can block all signals, all your devices in faraday bags will be 100% safe! Great Gift - Exquisite and numerous key fob signal blocker set will be a perfect gift choice to your friends and family. Attention: - Please make sure your device is put into inner layer since only the Inner layer blocks signals. - Remember to close the faraday key fob protector after putting key, phone, etc. Maintenance Method - Wipe with clean water. Avoid dry cleaning, exposure to the sun, ironing and bleaching. QA About Handle Faraday Bag with Strap - Q: What is a Faraday Bag? - A: The faraday bag can block the passage of radio signals when you put phones/laptop/car key remote in faraday pouch. - Q: How Does The Key Fob Signal Blocker Case Stop Thieves? - A: Thieves steal the code from the remote key by broadcasting a radio signal to it, then capture and decrypt the frequency and pair it with the car's locking system to unlock the car. By putting your car key into faraday bag and then close the velcro, the key's frequency is 100% isolated and undetectable by thieves, promoting car security at the same time protect privacy. - Q: How to test the faraday pouch works? - A: The way to test that the faraday key fob protector work or not is to put your key into the faraday bag and press the button while next to the car. If the car is not responsive, then this faraday cage does block the signal. You can also put your phone and laptops to test. - Q: How to Use This Faraday Cage Correctly? - A: Step 1 - Put your key, phone inside the rear gold cage. Step 2 - Closed velcro on the faraday bags.