What appears to be a second fourth-generation iPhone prototype has been purchased and disassembled, with pictures posted online. Mac Rumors reports that the submission they received said the unit was purchased by a Vietnamese businessman along with an iPad; the photos were originally posted on a Vietnamese forum. The shots confirm that this particular unit is operational, and is running some sort of firmware diagnostics program. Notably, the unit has no screws on the bottom and is labeled on the back as a 16GB model; it appears otherwise identical to the unit acquired and photographed by Gizmodo last month. The teardown shots also show an Apple-branded processor inside, which Engadget, citing Chipworks, claims is an Apple A4 processor, similar if not identical to the one found in the iPad.