14 rds With a pearce +1 this spring is perfect. G30 users using 13 rd g21 mags need this. G30 requires more spring power to assist feeding and although the g21 works decently with oem spring, there is possible ftf with +p or super rounds. I have a G30s 45super.

I did 460 Rowland conversions on both of my 45 caliber Glocks, and I wanted to be able to keep more than 13 Rounds in the magazines, so I picked up some +4 magazine extensions and installed these Springs in there and they work fantastic. No feeding issues whatsoever. Great product, at a great price!