X-50 Hardware to QCW

I recently purchased a X-50 with the QCW frame.
While assembling and mounting the Y rails to the QCW I found only 15 of the 16 needed bolts that secure the y rail to the frame. Can someone Tell me what the pitch and thread of those bolts are? When I called Onefinity they told me to go to the forum and ask. Actually he told me to surcharge by commonly used hardware…

M5 thread, 16 long, with a 5mm hex socket head.