This is the Mec-Gar SIG P226 9mm 20-round extended magazine.

Complete with Mec-Gar’s signature Anti-Friction Coating (AFC) to prevent corrosion and increase loading speed.

Also, this magazine features Mec-Gar’s +2 magazine extension, bringing the capacity to 20 rounds. 

Mec-Gar magazines are some of the highest-quality aftermarket magazines available for Sig Sauer handguns.