No doubt about it, Alphonse's Lakeline metal follower for Kahr 9mm magazines works like a charm, but I'm usually pleased when I can acquire one of the "MK" marked magazines with the old folded steel follower. I just received this one from an Ebay auction and it looks as if it might never have been used:)
https://s15.postimg.cc/m8smzk1uj/mag800.jpg
I've yet to have an issue with these mags in my MK9.
Regards,
Greg