This is the Mec-Gar SIG P228 9mm 18-round extended magazine.

This also fits older P229 pistols that accepts a flat-sided narrow magazine.

This will not fit P229 E2 pistols with accepts a wider-tapered P229-1 magazine.

• Increased capacity to 18-rounds with “Plus-3″ Adapter – only 5/8” longer than flush-fit magazines
• Carbon Steel Tube, heat-treated for strength with Anti-Friction Coating allows for easy loading and superior anti-corrosion
• Higher tensile music wire spring
• Polymer follower
• Removable steel butt-plate
• Interlinked internal components