C-Prod. mag's use their own "anti-tilt" follower, but it doesn't work. 3 out of 3 I got will tilt and jam with ease if you try to push them down with a screwdriver or something. The ones I got from them a long time ago with Magpul follower's work flawlessly. You can push the follower's all the way down all you want with no jam's.
I called Magpul to try and buy some follower's, they said they don't sell them anymore, only to PRI and I could get some there. So I called PRI and they said yep, how many do you want? I got a bunch of them, went to put one in and found out..... they don't fit any other mag, only PRI! Something both Magpul & PRI "forgot" to tell me. So... back they go.
It still amazes me that C-Products would have a real good mag useing Magpul follower's, and to save a $1 (or less) they would switch to a cheap one. I would much rather pay them another dollar or two for the one's with Magpul.