I'm onboard with getsome's excellent advice in regards to contacting Lakeline about the 9mm follower. I also agree that they work very well. I stiil use them in some of my magazines.
I use MagGuts' product in my other magazines. They are a few dollars more, but work very well and add capacity: https://magguts.com/product-category/kahr/kahr-kahr/
Regards,
Greg