The Mec-Gar Plus-2 Adapter Set for Sig P320 full-size 9mm magazines (Mec-Gar part no. F42270SET) is a replacement floorplate set that increases the capacity of Sig Sauer factory P320 full-size 9mm magazines by two rounds. The kit contains a polymer Plus-2 magazine extender and a phosphate steel locking plate that is heat treated. It is built only for the factory Sig magazines named, so it is a targeted upgrade for a P320 owner who wants more rounds from magazines already on hand.

Key Specifications

• The set is made for Sig Sauer factory P320 full-size 9mm magazines only, so it is not a universal part.
• It is a Plus-2 design, which raises magazine capacity by two rounds.
• The kit includes one polymer Plus-2 magazine extender, the piece that adds the extra length.
• It also includes one phosphate steel locking plate, heat treated, which holds the extender in place.
• It works as a replacement floorplate set, so it swaps for the base already on the magazine.

Frequently Asked Questions

Which magazines does this adapter set fit? Mec-Gar makes it for Sig Sauer factory P320 full-size 9mm magazines only.

What comes in the kit? One polymer Plus-2 magazine extender and one heat-treated phosphate steel locking plate.

How much capacity does it add? It is a Plus-2 set, so it adds two rounds to the factory magazine.

Buy the Mec-Gar Plus-2 Adapter Set for Sig P320 Full-Size 9mm Magazines

Two extra rounds from magazines you already own is a low-cost upgrade for a full-size P320. Order the set from our Lubbock, Texas gun shop for fast, insured shipping, and see more magazine accessories from Mec-Gar.