For those that don't understand how it works, see the piece that goes on his ears? The CD is in that piece, so, when he sticks his head forward, it slides up that piece up until the turn, where it makes that turn. Then when he tilts it backward, it will slide back down, but down is harder with that turn so he goes completely back. You can try to do this, but it may not work due to how your glasses are made.
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