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Choate Tool Mossberg Magazine Extension Up to 11% Off w/ Free S&H — 9 models

Choate Tool Mossberg 835/590 +1 Matte Magazine Extension, CMT-02-04-11
Choate Tool Moss. 930-935- 1Shot P, 4 1/4, CMT-02-04-01
Choate Tool Moss. 8-Shot Magazine Extension, Matte, CMT-02-04-08
Choate Tool Moss. 835-7 Shot Magazine Extension, CMT-02-04-12
Choate Tool Moss. 930 - 9 Shot Magazine Extension Matte, CMT-02-04-34
Choate Tool Moss. 835-9 Shot Magazine Extension, CMT-02-04-14
Choate Tool Moss. 835-8 Shot Magazine Extension, CMT-02-04-13
Choate Tool Moss. 930 - 10 Shot Magazine Extension Matte, CMT-02-04-35
Choate Tool Mossberg 835-10 Shot Extension, CMT-02-04-15
Choate Tool Moss. 930 - 9 Shot Magazine Extension Matte, CMT-02-04-34
Choate Tool Moss. 930 - 9 Shot Magazine Extension Matte, CMT-02-04-34
Choate Tool Mossberg 835/590 +1 Matte Magazine Extension, CMT-02-04-11
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Choate Tool Mossberg 835/590 +1 Matte Magazine Extension, CMT-02-04-11
Choate Tool Moss. 930-935- 1Shot P, 4 1/4, CMT-02-04-01
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Choate Tool Moss. 930-935- 1Shot P, 4 1/4, CMT-02-04-01
Choate Tool Moss. 8-Shot Magazine Extension, Matte, CMT-02-04-08
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Choate Tool Moss. 8-Shot Magazine Extension, Matte, CMT-02-04-08
Choate Tool Moss. 835-7 Shot Magazine Extension, CMT-02-04-12
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Choate Tool Moss. 835-7 Shot Magazine Extension, CMT-02-04-12
Choate Tool Moss. 930 - 9 Shot Magazine Extension Matte, CMT-02-04-34
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Choate Tool Moss. 930 - 9 Shot Magazine Extension Matte, CMT-02-04-34
Choate Tool Moss. 835-9 Shot Magazine Extension, CMT-02-04-14
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Choate Tool Moss. 835-9 Shot Magazine Extension, CMT-02-04-14
Choate Tool Moss. 835-8 Shot Magazine Extension, CMT-02-04-13
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Choate Tool Moss. 835-8 Shot Magazine Extension, CMT-02-04-13
Choate Tool Moss. 930 - 10 Shot Magazine Extension Matte, CMT-02-04-35
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Choate Tool Moss. 930 - 10 Shot Magazine Extension Matte, CMT-02-04-35
Choate Tool Mossberg 835-10 Shot Extension, CMT-02-04-15
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Choate Tool Mossberg 835-10 Shot Extension, CMT-02-04-15
Choate Tool Moss. 930 - 9 Shot Magazine Extension Matte, CMT-02-04-34
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Choate Tool Moss. 930 - 9 Shot Magazine Extension Matte, CMT-02-04-34
Choate Tool Moss. 930 - 9 Shot Magazine Extension Matte, CMT-02-04-34
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Choate Tool Moss. 930 - 9 Shot Magazine Extension Matte, CMT-02-04-34

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Questions & Answers
I have a mossberg 500 12g 18.5” with a breacher. Will this magazine + 1 fit and will it line up with my barrel? Expert Answer

The Choate Tool Mossberg Magazine Extension will fit flush with that shotgun.

by Hunter, Gear Expert, August 12, 2022
See 3 More Answers
Will it line up with the barrel of a six shot tube on a Mossberg 590 or will it go pass Expert Answer

The +1 Choate Tool Mossberg Magazine Extension for the Mossberg 590 should not pass the barrel.

by Hunter, Gear Expert, December 6, 2022
View All Q&A You Have a Question? Ask!
Customer Reviews
Helpful Negative Review
It works but not with new follower. by Littleoutpost, July 21, 2022
Can’t fit a 7th shell in if you use the provided follower. Use the original one and you can barely get a seventh shell in but it works. Goes past a 18.5 inch barrel by about one inch. Since optics planet won’t let you post a review without there bein...
Read More...
17/17 found this helpful
Most Recent Reviews
Extends past barrel by Moss590, Verified Owner, June 15, 2026
This +1 extension extends almost a full inch past the barrel of my 590 even though it says it should be flush.
1/1 found this helpful
Most Recent Reviews
works good by ben, Verified Owner, April 5, 2026
Good for an 18” 990 aftershock. Ended up 1/4” shy of the barrel and added +1 capacity. Quality is great and the price is reasonable
Most Recent Reviews
Not a correct fit. by Eric, Verified Owner, March 3, 2026
The threads on the extension did not grab on and the extension flew off under recoil causing my gun to disassemble itself at the range. Not worth having 1 more shell but sacrificing reliability.
Most Recent Reviews
Perfect upgrade to the Mossberg 590S by Xyphon, Verified Owner, January 9, 2026
Perfect upgrade to add +1 capacity to the magazine tube. Fits the 590S perfectly and is very easy to install. Personally I still only load at the original capacity. Saves the spring and gives me options if I need it.
Most Recent Reviews
Mossberg 590 + 1 tube extension by Mossberg plus 1 extension, Verified Owner, May 12, 2024
Solid quality. The plus 1 cap is indexed (on the bottom) like the original 590 cap so when you screw the cap onto the tube the cap locks solid and tight on the tube with the detent ball on the barrel (magazine) lug. Can’t go wrong with the pricing ei...
Read More...
Read All 8 Reviews
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9 Models Available
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made-in-usa-flag Made in USA

Help support American manufacturing! Marked models of this product have gone through rigorous review and been certified by the manufacturer as Made in the USA.

Product Info for Choate Tool Mossberg Magazine Extension

If you're shopping for a great price on the Choate Tool Mossberg Magazine Extension, then you've found yourself in the right place..image

Formulated by using several of the most sturdy and long lasting substances in existence, these Shotgun Magazine Extensions from Choate Tool provides you with an item which will give numerous years of consistency.

Choate Tool has been generating top quality products for a number of years, and the Choate Tool Mossberg Magazine Extension is their very own manner of showing you just how much they are concerned.

Here at OpticsPlanet, we make it our responsibility to get the most suitable solution for all of your requirements, and exhibiting the Choate Tool Mossberg Magazine Extension is a thing that we are happy to offer.

Specifications for Choate Tool Mossberg Magazine Extension:

Manufacturer: Choate Tool
Caliber: 12 Gauge
Condition: New
Country of Origin: USA

Features of:

  • Adds one shotshell
  • Steel construction

Package Contents:

  • Choate Tool Mossberg Magazine Extension
  • Mag extension
  • Mag tube spring
  • High visibility shell follower

What firearm models does the manufacturer say Choate Tool Mossberg Magazine Extension is compatible with?

The manufacturer says that Choate Tool Mossberg Magazine Extension is compatible with Mossberg Model 590, Mossberg Model 835, Mossberg Model 930

Choate Tool Mossberg Magazine Extension Orderable Models

List of Orderable Models

  • Choate Tool Mossberg 835/590 +1 Matte Magazine Extension, CMT-02-04-11 , MPN: CMT-02-04-11 , Code: OP3-MZX-CHTL184-CMT-02-04-11-1RD
  • Choate Tool Moss. 930-935- 1Shot P, 4 1/4, CMT-02-04-01 , MPN: CMT-02-04-01 , Code: OP3-MZX-CHTL184-CMT-02-04-01-1RD
  • Choate Tool Moss. 8-Shot Magazine Extension, Matte, CMT-02-04-08 , MPN: CMT-02-04-08 , Code: OP3-MZX-CHTL184-CMT-02-04-08-8RD
  • Choate Tool Moss. 835-7 Shot Magazine Extension, CMT-02-04-12 , MPN: CMT-02-04-12 , Code: OP3-MZX-CHTL184-CMT-02-04-12-7RD
  • Choate Tool Moss. 930 - 9 Shot Magazine Extension Matte, CMT-02-04-34 , MPN: CMT-02-04-34 , Code: OP3-MZX-CHTL184-CMT-02-04-34-9RD
  • Choate Tool Moss. 835-8 Shot Magazine Extension, CMT-02-04-13 , MPN: CMT-02-04-13 , Code: OP3-MZX-CHTL184-CMT-02-04-13-8RD
  • Choate Tool Moss. 835-9 Shot Magazine Extension, CMT-02-04-14 , MPN: CMT-02-04-14 , Code: OP3-MZX-CHTL184-CMT-02-04-14-9RD
  • Choate Tool Moss. 930 - 10 Shot Magazine Extension Matte, CMT-02-04-35 , MPN: CMT-02-04-35 , Code: OP3-MZX-CHTL184-CMT-02-04-35-10RD
  • Choate Tool Mossberg 835-10 Shot Extension, CMT-02-04-15 , MPN: CMT-02-04-15 , Code: OP3-MZX-CHTL184-CMT-02-04-15-10RD

Choate Tool Mossberg Magazine Extension Unavailable & Discontinued Models

List of Unorderable Models

  • USED Choate Tool Moss. 930-935- 1Shot P, 4 1/4, CMT-02-04-01, EDEMO3, Used, Condition Fair , MPN: CMT-02-04-01-EDEMO3 , Code: OP3-MZX-CHTL184-CMT-02-04-01-1RD-EDEMO-US-D
  • USED Choate Tool Moss. 930-935- 1Shot P, 4 1/4, CMT-02-04-01, EDEMO1, Used, Condition Fair, Missing Item , MPN: CMT-02-04-01-EDEMO1 , Code: OP3-MZX-CHTL184-CMT-02-04-01-1RD-EDEMO-MI-D
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Last updated 2026-09-20 UTC.