Apple iPhone 5 Rear Cover VideoIt appears Tim Cook’s memo on “doubling down” on security hasn’t reached everyone just yet, as a parts supplier in China has posted a video where they take a long, hard look at what could be the shell from an iPhone 5.

The part on display looks to be identical to the one leaked at the end of last month, complete with two-tone color scheme, repositioned 3.5mm headphone socket, new speaker grill arrangement and a smaller dock connector.

This hands-on has revealed a few more changes too. The shell is slightly thinner and has the same width as an iPhone 4, but is noticeably longer, adding weight to the persistent rumors the next generation iPhone model will have a bigger screen, potentially measuring 4-inches, while maintaining a 640 pixel width.

The narrator also notes that the new piece is a single part, rather than the rear plate and the chassis’ skeleton being two separate pieces as with the iPhone 4, and that it’s made from aluminum. If this is the iPhone 5, it looks like Apple has admitted defeat on trying to convince us an almost all-glass device is a good idea.

Another alteration comes when looking at the SIM card tray, as the piece which fits the new part is too small to fit in the iPhone 4. Earlier this week, an Apple-submitted design for a new, smaller nano-SIM was approved by ETSI, although the chances of Apple having enough time to integrate this into the new iPhone are slim.

It’s impossible to say whether the part seen in the pictures and video is representative of the final design for the next generation iPhone. Before the unveiling of the iPhone 4S, pictures showing an alternative design for the phone were widely circulated, and obviously didn’t turn out to be accurate.

There’s little to suggest this is any different, but even if it is fake, or one of Apple’s many prototypes for the next iPhone, it’s still an interesting conversation piece.