I can't tell you for sure but I can give you a warning:
Until you hear from someone who knows, do NOT unscrew the screw all the way !!! :shock:
On a lot of models, they have a rubber expansion plug that holds them in; to remove, you just need to loosen the screw until it is not tight anymore and the pull the whole assembly out.
If your's work that way and you take the screw all the way out, the parts of the expansion assembly (nut and washers) fall off inside the bars and are sometimes hard to retrieve.