The Tyrant CNC Magazine Extension, also known as base pads, is designed to increase the ammunition capacity of Springfield Armory Echelon's 15 and 17-round magazines by an additional 5 rounds of 9mm. This upgrade is essential for users looking for more capacity without sacrificing the firearm's reliability and performance. Features : Color: Gold Designed for Springfield Echelon Fits on 15/17 round Echelon Magazines +5 Capacity of 9mm No tools required for installation