So i was going to adjust the action on my old guitar, but when i went to do it, i noticed that the two screws on either side of each saddle had no heads. I know an allenwrench is supposed to be used, but there is no hex head that can be gripped by the allen wrech.

I have all sizes of them, but none work because there is no hex head to grab onto. The is also no head for a screw driver to fit, so i have no idea what to do. Its like the top of the screw is just flat.

When I first got it, there was some fret buzz on the low e, so I took it into the shop to have the action raised. They said it would take an allenwrench to do. They adjusted it (I didnt see them do it), and they somehow raised it, so there has to be some way.
Gibson SG Standard
Ibanez S2170FB
Peavey JSX
Marshall 1960A