Thank you for viewing. This was a gift, but I'm selling it because I don't use it. I opened the box and tried it on once. I think the magnetic force is strong. It supports MagSafe, so it can be used with compatible iPhones or cases. For smartphones or cases that do not support MagSafe, you can use the included metal ring shown in the third photo. There is a mark where the sticker was peeled off on the back of the box (see photo 5). Please refrain from purchasing if you are sensitive to used items or are particular about details, as this is a personally owned used item. MagSafe iPhone Android Smartphone ring 360-degree rotation Bunker ring Magnet ring