It looks like Prodisc to me.
For one, CMC doesn't use foam to cushion their discs. Prodisc and now RiTEK do that.
Secondly, CMC don't generally use cakeboxes with shiny black bases. Prodisc and MBI use these cakeboxes, but the MBI cakeboxes have RiTEK-like covers.
Thirdly, check if the discs are wrapped in a roll inside the spindle. RiTEK and Prodisc do that to their discs to prevent them front spinning around inside the cakebox. MBI, Taiyo Yuden, and CMC do NOT wrap their discs in this way and if you carefully turn the cakebox, discs move seperately from one another.
Hope that helps!