Easy to Use - The stickers can be pasted on mobile phones, laptops, tablets, PCs, TVs and other small electronic devices. Just stick the stickers on the back of your phone or the surface of your electronic device. Effectiveness - Each sticker can safely shield EMF/EMR generated by mobile phones, laptop safes, tablets, PCs, TVs and other small electronic devices. What it does - Ordinary electronic devices usually emit EMF (electromagnetic frequency) and EMR (electromagnetic radiation), which are harmful to the human body. Our mobile phone protection sticker shielding adopts magnetic negative ion technology, which can absorb and neutralize ions in EMF/EMR. Slim Size: The thin body is not enough to make your phone heavy, and the new ultra-thin design allows you to put it on your phone or any other electronic device. You can take it with you Protect you and your family from radiation. Type: EMF protection sticker Color: Silver Material: Silicone Size: 28 mm in diameter Package Contents: 20 x Stickers Above package contents only, other products are not included. Note: Light and different monitors may make the color of the item slightly different from the actual object. The measurement allowable error is +/- 1-3 cm.