63-S006 Silver Metal 3.0 USB Flash Drive, Portable Waterproof Metal Pen Drive Storage Keychain Thumb Drive Memory Stick with Anti-Lost Keychain (512GB)

So many of these keychain flash drives have bad reviews and this one is no different. Its unfortunate as I liked the design and feel of the devise. I was trying to transfer some folders to it and the files failed to transfer at 8.5G. After that, every time I tried to repair the disc or reformat, it will error and unmount. Ive tried on Mac and windows, nothing. I have been using portable media since floppies, so I know what I am doing, this drive is just poor quality.