These round and square metal plates perfectly work along with all magnetic mounts. They have strong adhesive on the back. It will not come off and no sticky residual after detaching. Powerful magnetic keeps your device stable and secure while driving. Great to use with smartphones and tablets magnet mounts. Features - Color: Black - Material: Iron. - Size: 6.5 x 4.5 x 0.2 cm. - Square and round metal magnetic plates to attach device onto magnet mounts. - Great to use with smartphones and tablets magnet mounts. - The magnetic plate mount easily sticks to the back of devices for easy mounting. - Works with magnet mounts designed to hold devices with the metal plate. - These mount metal plates themselves are not magnetic, but they can work with all magnetic car mount phone holders. - Warm Tip: Dear buyer, Due to lighting effect, monitor's brightness, manual measurement and etc, there could be some slight differences in the color and size between the photo and the actual item. Sincerely hope that you can understand! Thank you! Package list: 12 Metal Plates