Aluminum case by Signal Protector Reliable protection against theft of your car on the so-called "suitcase" . Principle of operation The product works on the principle of a Faraday cage. As long as the key is in a closed case, there is no way for the signal to get outside. Thanks to this, a potential thief will not intercept the signal from your key. The case effectively blocks the signal emitted by the keys of all car brands. Reliable protection The product was created for the most demanding users. The aluminum case eliminates the possibility of abrasion of the signal-blocking material used in traditional anti-theft cases. Thanks to this, the product will serve you for many years. Product features: Material: aluminum Colour: black External dimensions: 8.6 cm x 5.5 cm x 2.8 cm Internal dimensions: 7.9 cm x 4.2 cm x 2.3 cm (please compare with the dimensions of the key) - The wall thickness at the narrowest point is 3 mm, which makes it very resistant to deformation and perfectly blocks the signal - The case is lined inside with a pleasant to the touch material that prevents the key from scratching - It has a profile for the thumb, making it easy to open with one hand - The use of magnets protects against uncontrolled opening of the case, facilitates closing Factory packed by the manufacturer. Comparison of the size of the Signal Protector aluminum case with other products in the series. ATTENTION! Correct arrangement of the key in the case: the top of the key on the bottom of the box. It is also worth remembering to secure the spare key, as its signal can be intercepted, even if it is at home. Note: Due to the light and screen setting difference, the item's color may be slightly different from the pictures. Please allow slight dimension difference due to different manual measurement.