I prefer the XTECH Tactical + 2 mag extension. Comes with dedicated spring. Easy, no tools & no extra screw installation, works great and co$t$ $20 vs Maguts & others co$ting $30+. Converts 8 shot mag to 10 or 7 mag to 9. Then with one in chamber & mag "topped off" gives 10 to 11 capacity. Worth checking out.