The KRISS magazine extension kit (manufacturer part number KVA-MX2K45BL00) is an accessory that extends a compatible Glock G21 magazine to a 30-round total capacity. It is not a standalone magazine and does not include a complete magazine body.

Key Specifications

• Extends a compatible Glock G21 magazine to a 30-round total capacity.
• Built for .45 ACP-caliber magazines.
• Manufactured by KRISS.
• This is an extension kit only — it does not include a complete magazine body, and is not itself a standalone magazine.
• Weighs about 0.3 lb shipped.
• Ships in retail packaging measuring about 1.3 by 6.0 inches.
• The .45 ACP chambering is short for .45 Automatic Colt Pistol.
• Always confirm compatibility with your specific magazine’s generation/model before ordering.

Frequently Asked Questions

Does this include a complete magazine? No — this is an extension kit only. It’s designed to increase the capacity of a compatible factory magazine you already own; it does not include a full magazine body.

What does this fit? It’s built for Glock G21 .45 ACP magazines, extending them to 30 rounds total. Confirm exact compatibility with your specific magazine before ordering.

Buy the KRISS Mag-Ex2 Extension Kit for Glock G21 (.45 ACP)

Ships fast from a Lubbock, TX gun shop on the KRISS Mag-Ex2 Extension Kit for Glock G21 (.45 ACP) from KRISS, part of our Magazine Accessories selection. Pick up a genuine capacity upgrade for your compatible magazine.