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Questions & Answers
Is this compatible with the 21 & 17 round magazines? Manufacturer Answer

The Sig P320 magazine extension will work on the 17 round magazines. If you install it on a 21 round magazine you will need to upgrade your spring to a +Power Spring, and you will likely still have some rattling.

by KillerInnovations, Manufacturer, November 20, 2024
Will this work on the p320 XTen or just the 9mm mags? Manufacturer Answer

This will not work on P320 X-Ten magazines, they are compatible with 9mm and .40 S&W only.

by Killer Innovations, Manufacturer, August 13, 2025
Customer Reviews
Helpful Positive Review
Great product by Robert, Verified Owner, November 16, 2024
The only reason I don't give this 5 stars is be cause they say the gold color is gold but it definitely isn't its more like an off color of orange but no where near the gold color. Because of this I had to opt for a different brand which really suck...
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1/1 found this helpful
Most Recent Reviews
Will come loose on you by JD, Verified Owner, March 13, 2025
I took this to the range a couple times and the entire base came loose. I have the tiny set screw as tight as can be without stripping it and it is loc-tited. Do not buy this if you value dependability.
Most Recent Reviews
Does what it should, looks good. by JP, Verified Owner, January 20, 2024
Fits, stays put, and looks great. I have this on a 15rd mag, xcompact frame, Agency Arms build.
Read All 3 Reviews
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Product Info for Killer Innovations Sig P320X Magazine Extension

Outfit your handgun with a rugged and reliable Killer Innovations Sig P320X Magazine Extension to increase your ammo capacity and stability in the field. Killer Innovations machined these Magazine Extensions from 6061 T6 aluminum for a rugged yet lightweight structure that won't weigh you down at the range or in the field. This Killer Innovations Velocity Mag Extension also contains their patented 'Enhanced Grip Features' cuts that provide a serrated gripping surface to assist your reloads - giving you the ultimate control while creating a smooth and seamless experience while doing so. Using the toolless floorplate removal method, you can easily remove the mag extension without a tool - allowing for a simple mag clean down. Get your Killer Innovations Velocity Magazine Extension to increase your ammo capacity and stability with your SIG P320X pistol.image

Specifications for Killer Innovations Sig P320X Magazine Extension:

Manufacturer: Killer Innovations
Fabric/Material: 6061-T6 Aluminum
Finish: Anodized
Magazine Capacity: 5 Round
Gun Make: SIG Sauer
Gun Model: SIG Sauer P320
Condition: New

Features of Killer Innovations Sig P320X Magazine Extension

  • NOT COMPATIBLE WITH 10 ROUND MAGS

Package Contents:

  • Killer Innovations Sig P320X Magazine Extension

Killer Innovations Sig P320X Magazine Extension Orderable Models

List of Orderable Models

  • Killer Innovations Sig P320X Magazine Extension, Gray, SIGME309GRY , MPN: SIGME309GRY , UPC: 810104450096 , Code: 3P4-PME-KILI20-SIGME309GRY-5RD
  • Killer Innovations Sig P320X Magazine Extension, Fde, SIGME309FDE , MPN: SIGME309FDE , UPC: 810104450072 , Code: 3P4-PME-KILI20-SIGME309FDE-5RD
  • Killer Innovations Sig P320X Magazine Extension, Gold, SIGME309GLD , MPN: SIGME309GLD , UPC: 810104450089 , Code: 3P4-PME-KILI20-SIGME309GLD-5RD
  • Killer Innovations Sig P320X Magazine Extension, Orange, SIGME309ONG , MPN: SIGME309ONG , UPC: 810104450102 , Code: 3P4-PME-KILI20-SIGME309ONG-5RD
  • Killer Innovations Sig P320X Magazine Extension, Blue, SIGME309BLU , MPN: SIGME309BLU , UPC: 810104450065 , Code: 3P4-PME-KILI20-SIGME309BLU-5RD
  • Killer Innovations Sig P320X Magazine Extension, Red, SIGME309RED , MPN: SIGME309RED , UPC: 810104450119 , Code: 3P4-PME-KILI20-SIGME309RED-5RD
  • Killer Innovations Sig P320X Magazine Extension, Black, SIGME309BLK , MPN: SIGME309BLK , UPC: 810104450058 , Code: 3P4-PME-KILI20-SIGME309BLK-5RD

Killer Innovations Sig P320X Magazine Extension Unavailable & Discontinued Models

List of Unorderable Models

  • USED, Killer Innovations Sig P320X Magazine Extension, Fde, SIGME309FDE , MPN: SIGME309FDE-EDEMO , Code: 3P4-PME-KILI20-SIGME309FDE-5RD-EDEMO-SC-B
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