Stronger Magnets: This mag safe wallet features an N52 ultra-strong magnet (strength up to 4200 Gauss) built in to provide a powerful hold and prevent your phone from falling off. Magnetic Mag-safe Wallet Cell Phone Card Holder for Phone Case with Mag-Safe, Stronger Magnetic RFID Leather Phone Wallet Stick on for iPhone 17/16/15/14/13/12 Series, Black Color.