Another Rival-S optic question.

What optic besides the M03 Mechanic can direct mount so we don't have to use a plate..any Holosun direct mount?? .and for the Rival-S if we use plates. What are the threads for the plates to mount the optics to? Mine did not come with any screws? How far past the bottom of the optic should the screw length be? Or what is the max length of screw past the optic base?