Interesting design. I saw a post about 5 years ago where the poster called it a flat spring. Not sure what kind of spring that is. Did some research and found nothing. I wonder if the fatigue rate is the same as the coil spring. When does Magguts recommend time to change out the magazine (round count), I also noticed on a video of the 365 15 round magazine, Magguts is just ONE piece not two different springs. They use the Flat spring only. Seems like this would be more attractive to owners of the Kahr's if it were one spring, instead of the weird two piece.

PS Just checked my magazines and it seems I do have one Magguts and working fine. I will check the 9mm later.

https://www.youtube.com/watch?v=7lsRfs9TWjA&t=12s