What is the S15 +2 Pre-Installed Magazine Extension?
The S15 +2 Pre-Installed Magazine Extension is a factory-assembled package combining our S15 Gen 3 Magazine with a professionally installed +2 magazine extension, delivering 17+1 total capacity for your Glock 43X or 48. This pre-installed option eliminates installation concerns and ensures perfect fitment right out of the package.
Key Components & Requirements:
Factory Pre-Installed for Immediate Use
The S15 +2 Pre-Installed Magazine Extension represents the perfect solution for shooters who want maximum capacity without the hassle of self-installation. This factory-assembled package combines our patented S15 Gen 3 Magazine with a precision-installed +2 magazine extension, delivering an impressive 17+1 total capacity. Each unit is professionally assembled by our team to ensure optimal performance and reliability from the first round.
Constructed from precision-machined billet 6061 aluminum with Type-2 anodized finish options, the S15 +2 extension adds just two rounds while maintaining a low-profile footprint suitable for concealed carry. The extension features our innovative easy-access floor plate design that allows for cleaning and maintenance without complete removal, plus index cuts machined into the body for improved grip when drawing from magazine pouches. An upgraded 11-coil power spring ensures consistent feeding pressure across all 17 rounds.
This pre-installed configuration is ideal for concealed carry professionals, competitive shooters, and anyone who demands the highest capacity from their Glock 43X or 48 without adding significant bulk. The combination maintains compatibility with most aftermarket flared magwells and works seamlessly with Shield Arms Carry and Premium Magwells for optimized reloads.
Key Features
- 17+1 Total Capacity - Extra rounds for concealed carry for Glock 43X/48
- Factory Pre-Installed - Professionally assembled and tested before shipping
- Precision-Machined Construction - CNC-machined from billet 6061 aluminum for lightweight durability
- Type-2 Anodized Finish - Available in multiple color options with superior corrosion resistance
- Easy-Access Floor Plate - Unique design allows cleaning and servicing without complete extension removal
- Enhanced Grip Index Cuts - Machined cuts improve tactile feedback when drawing from pouches
- 11-Coil Power Spring - Upgraded spring ensures reliable feeding across extended capacity
- Black Nitrocarburized QPQ Finish - Superior wear resistance on magazine body
- Magwell Compatible - Works with Shield Arms Carry/Premium Magwells and most aftermarket flared magwells
- Patented Design - Exclusive Shield Arms engineering backed by U.S. patents
- Made in USA - Manufactured and assembled in the United States
Critical Requirements for S15 Magazine System
Steel Mag Catch Required: The S15 magazine system requires replacing your plastic OEM mag catch with a Shield Arms steel mag catch (standard or premium). Using another manufacturer's catch or the OEM plastic catch will result in reliability issues and potential magazine drop failures. S15 magazines are engineered specifically to work with Shield Arms steel mag catches.
The enhanced capacity and steel construction of S15 magazines create different lock-up geometry that requires the increased strength and precision of our steel catch design.
Warranty & Manufacturing Quality
Every S15 +2 Pre-Installed Magazine Extension is backed by our 100% lifetime warranty against manufacturing defects. Additionally, all Shield Arms magazine products include our exclusive "Spring for Life" guarantee - if you ever wear out your magazine spring, we'll replace it free of charge for the life of the product. Proudly manufactured and assembled in the USA using premium materials and precision CNC machining.
Technical Specifications
| Specification |
Details |
| Total Capacity |
17+1 rounds (15+2 in magazine) |
| Compatible Models |
Glock 43X, Glock 48 |
| Extension Material |
Billet 6061 Aluminum |
| Extension Finish |
Type-2 Anodized (multiple color options) |
| Magazine Body Finish |
Black Nitrocarburized QPQ |
| Spring Type |
11-coil power spring |
| Base Length |
Same as OEM Glock 43X/48 magazine base |
| Magwell Compatibility |
Shield Arms Carry/Premium Magwells, most aftermarket flared magwells |
| Required Accessory |
Shield Arms steel mag catch (sold separately) |
| Country of Origin |
Made in USA |
| Warranty |
Lifetime + Spring for Life guarantee |
Comparison: S15 +2 Pre-Installed vs OEM Glock Magazine
| Feature |
S15 +2 Pre-Installed |
OEM Glock 43X/48 |
| Total Capacity |
17+1 rounds |
10+1 rounds |
| Magazine Body Material |
Steel with QPQ finish |
Polymer |
| Extension Material |
Billet aluminum (pre-installed) |
Polymer baseplate |
| Additional Capacity |
+7 rounds |
Baseline |
| Easy-Access Floor Plate |
Yes - service without removal |
Standard disassembly required |
| Index Grip Cuts |
Yes |
No |
| Mag Catch Requirement |
Shield Arms steel catch required |
Works with OEM plastic catch |
| Warranty |
Lifetime + Spring for Life |
Limited manufacturer warranty |
| Made in USA |
Yes |
Austria |
Frequently Asked Questions
What's included with the S15 +2 Pre-Installed Magazine Extension?
Each package includes one S15 Gen 3 Magazine with a professionally pre-installed anodized S15 +2 Magazine Extension in your choice of available colors. The extension features an 11-coil power spring and is fully assembled and ready to use. Note that the required Shield Arms steel mag catch is sold separately.
Do I really need to replace my OEM mag catch?
Yes, absolutely. The Shield Arms steel mag catch is mandatory for proper S15 magazine function. The OEM plastic catch was designed for lighter polymer magazines and cannot reliably retain the heavier steel S15 magazines. Using the OEM catch or another manufacturer's catch will result in magazine drop failures and reliability issues. Only Shield Arms steel mag catches are engineered to work with S15 magazines.
What is the advantage of buying the pre-installed version?
The pre-installed version saves time and eliminates installation concerns. Our team professionally installs and tests each extension to ensure optimal fitment, spring tension, and reliability. This is ideal for shooters who prefer factory-assembled products or want immediate use without self-installation. Each unit is inspected before shipping to guarantee proper function.
Will this work with my aftermarket magwell?
The S15 +2 Pre-Installed Magazine Extension is designed to work with Shield Arms Carry and Premium Magwells, and fits most aftermarket flared magwells. However, compatibility can vary by manufacturer. We recommend checking with your magwell manufacturer or testing fitment if you're using a third-party magwell.
How does the easy-access floor plate work?
The S15 +2 extension features a unique floor plate design that allows you to access the magazine internals for cleaning or maintenance without completely removing the extension from the magazine body. This design makes field maintenance faster and reduces the risk of losing small parts during disassembly.
Are S15 magazines legal in my state?
Magazine capacity restrictions vary by state and local jurisdiction. The S15 +2 Pre-Installed Magazine Extension provides 17+1 total capacity, which may be restricted in some areas. It is the customer's responsibility to know and comply with all federal, state, and local laws regarding magazine capacity. Shield Arms ships only to addresses where such products are legal to own.
Can I add the +2 extension to my existing S15 magazines?
Yes, you can purchase the S15 +2 Magazine Extension separately and install it on your existing S15 magazines following our installation guide. However, the pre-installed version ensures factory-perfect installation and is ideal if you're purchasing a new magazine.
What colors are available for the anodized extension?
The S15 +2 extension is available in multiple Type-2 anodized color options. Available colors are displayed in the product options selector above. Please note that in 2025, the shade of the "Mud" color option was slightly updated, so previously purchased Mud-colored extensions may not exactly match new units.
What if my magazine spring wears out?
All Shield Arms magazines are covered by our "Spring for Life" guarantee. If your magazine spring ever wears out from normal use, contact us and we'll send you a replacement spring free of charge for the life of the product. This guarantee is in addition to our lifetime warranty against manufacturing defects.
Will the S15 magazine fit my Glock 43 (non-X)?
No, the S15 magazine is designed exclusively for the Glock 43X and Glock 48. It will not fit the standard Glock 43 due to differences in magazine well dimensions and grip length. The S15 magazine takes advantage of the longer grip frame of the 43X and 48 models.
Can I use the S15 magazine for competition shooting?
Absolutely. The S15 +2 Pre-Installed Magazine Extension is popular among competitive shooters who use Glock 43X/48 pistols in divisions that allow magazine capacity modifications. The 17+1 capacity provides a competitive advantage while maintaining a compact pistol footprint. Always verify your competition's equipment rules before match day.
How does Shield Arms test the pre-installed magazines?
Each S15 +2 Pre-Installed Magazine undergoes quality inspection after assembly to verify proper extension installation, spring tension, follower movement, and overall function. We ensure the extension is properly torqued and the magazine is ready for immediate use upon receipt.
Who Should Buy the S15 +2 Pre-Installed Magazine Extension
- Concealed Carry Practitioners - Maximize your defensive capacity without adding bulk to your EDC setup
- First-Time S15 Buyers - Get the complete magazine system assembled and tested from the factory
- Competitive Shooters - Gain additional capacity advantage in USPSA, IDPA, and other competition divisions
- Busy Professionals - Save installation time with factory-assembled magazines ready to use immediately
- Law Enforcement Officers - Increase on-duty capacity for Glock 43X/48 duty or backup guns
- Range Instructors - Reduce reload frequency during training sessions with students
- Backup Gun Carriers - Maximize capacity on your secondary concealed carry pistol
- Quality-Focused Shooters - Trust factory installation for optimal reliability and performance
Installation & Setup
The S15 +2 Pre-Installed Magazine Extension arrives fully assembled and ready to use. Simply install your Shield Arms steel mag catch, load your magazine, and you're ready to shoot. The required steel mag catch installation takes just minutes with basic tools. For detailed installation instructions for the mag catch and other Shield Arms products, visit our comprehensive installation guides page.
Complete Your S15 System - Related Products
Experience the Shield Arms Difference
The S15 +2 Pre-Installed Magazine Extension represents our commitment to innovation, quality, and customer satisfaction. With precision American manufacturing, lifetime warranty protection, and our exclusive Spring for Life guarantee, you're investing in a magazine system engineered to exceed expectations. Join thousands of satisfied customers who trust Shield Arms for their Glock 43X and 48 capacity solutions.
