Easy swap, does what it says, great price! - Pro Mag Springfield XD-9 Plus 4 / XD-40 Plus 3 Magazine Extension

For $10, adding an extra 4 rounds to my primary magazine for my XD-9 was a no-brainer, as was the very simple swap from the original base plate. Absolutely no issues; 1 minute of install, and an extra 4 rounds in the hoppa! AWESOME! I can't comment on build quality over time, but it seems robust enough.