I took the default Bolt Factory bolts and modified them. There are no threads as these are just the heads of the bolts for use in detailing and such.
I optimized the meshes by reducing the poly count of the default object and cleaning up the edges so the bit insets could be beveled nicely.
I also created a straight bit and star bit for each head type.
They are all UV unwrapped as well.
Hope they prove useful.