During a teardown at this year's DesignCon in Santa Clara, Calif., Kyle Weins, the CEO of iFixit, blasted Apple for switching out its Phillips screws for new tamper-resistant screws.
Weins, who has written a hardware manifesto stating that users should be allowed to tinker with their own devices, called the move "diabolical" on Apple's part.
"This is not a standard Torx, and there are no readily available screwdrivers that can remove it," he said, though iFixit has recently built a tool that can do the job. "Apple chose this fastener specifically because it was new, guaranteeing repair tools would be both rare and expensive."
Click the image below to view a slideshow of the iPhone 4S in various stages of disassembly:
The screw that Apple is using is similar to a Torx -- except that the points have a rounder shape, and the screw has five points instead of six.
Apple's service manuals refer to them as "Pentalobular" screws, which Weins admits is a fairly fitting description.
"This screw head clearly has one purpose: to keep you out," he said.