Hello everyone, I purchased a used bass a while ago that I am working on restoring. I repaired everything so far and simply need some screw sets. But I have one big problem. The neck is bowed a great deal. The E string is about a 1/4" inch away from the neck down by the body. I have no idea what type of bass it is, I have yet to figure that out. The truss adjustment is at the bottom of the neck by the body. It looks like there is an allen screw adjustment in the hole but I'n not sure. I tried various allen keys but none seemed to fit. Then I thought that you may just twist the piece sticking out w/ the holes through it. Is that simply what I do? Just curious, thanks everyone. I tried to twist it and it did move that way. Is that how I adjust the truss rod as opposed to using an allen key? Thanks. I attached a picture. Again I'd like to thank everyone for the help. Later.