XDM 9/40 ESP magwells are CNC machined from aluminum and anodized for durablity. This magwell was specifically designed to fit the IDPA box. The ESP magwell has enough room for an easy fast reload but ergonomically designed to make it easy to get back to your grip without interfere from the magwell. The unique attachment method requires that you grind the backstrap even with the top of the magwell opening or purchase a prefit #2 backstrap. This is for full sized XDM 9mm and .40 frames only.  For use with the #3 backstrap if you grind the back of the insert to fit the profile of the magwell.  Not recommended for use with #1 backstrap.  Does NOT fit with factory base pads, modification required to fit.  .953oz