What is the Custom S10 Series Glock 43X MOS?
The Custom S10 Series Glock 43X MOS is a factory Glock 43X MOS that has been precision-modified by Shield Arms to accept flush-fitting 10-round S10 magazines. Through expert CNC machining, the grip is trimmed to perfection and fitted with a custom S10 magwell and steel magazine catch, creating the ultimate deep concealment pistol without sacrificing capacity.
Key Components:
Ultimate Deep Concealment With No Compromise
The Custom S10 Series Glock 43X MOS represents the pinnacle of deep concealment pistol design. Starting with a factory Glock 43X MOS, Shield Arms applies precision CNC machining to modify the grip frame for perfect integration with flush-fitting S10 magazines. This custom modification creates a truly compact profile while maintaining a full 10-round capacity—ideal for situations where maximum concealment is paramount without sacrificing defensive capability.
Every Custom S10 build includes professional installation of the S10 magwell system and a black nitride standard steel magazine catch, ensuring flawless reliability with both S10 and S15 magazines. Each pistol is meticulously test-fired before leaving our facility and ships with two S10 10-round magazines. The result is a custom-built defensive tool that combines Glock reliability with Shield Arms innovation, purpose-built for concealed carry professionals and enthusiasts who demand the lowest possible profile.
Beyond the base platform, the Custom S10 Series offers multiple package configurations including upgraded AmeriGlo I-Dot night sights, threaded barrels for suppressor compatibility, and McNally trigger upgrades. Custom Cerakote finishes—including Fallout, Montana Mud, and Pineland patterns—are applied in-house, making each pistol truly unique. With build-to-order customization and FFL transfer handling, your Custom S10 arrives ready for duty straight from Shield Arms.
Key Features
- Precision CNC-Machined Frame - Professional grip modification for flush-fit S10 magazine integration
- Factory Glock 43X MOS Base - Optics-ready slide with precision cuts for micro red dots
- 10-Round Flush Capacity - Maximum concealment without sacrificing defensive rounds
- Steel Mag Catch Included - Black nitride standard steel magazine catch pre-installed
- S10 Magwell System - Purpose-built magwell for reliable S10 magazine function
- Full S15 Compatibility - Works seamlessly with entire S15 product ecosystem
- Test-Fired Reliability - Every pistol is function-tested before shipment
- Custom Package Options - Choose Enhanced, Pro-Carry, or Elite-Carry configurations
- In-House Cerakote - Multiple custom finish options applied by Shield Arms
- Glock Mounting Rail - Slim rail system for lights and accessories
- Match-Grade GMB Barrel - Gen5 Glock Marksman Barrel for enhanced accuracy
- Includes Two S10 Magazines - Ready for carry out of the box
Important Build Information
Custom Build-to-Order Process: Each Custom S10 Series pistol is built specifically for you. Due to the precision machining process and FFL transfer requirements, orders typically ship within 12-14 business days. This ensures every detail meets our exacting standards before your pistol leaves our facility.
Permanent Modification Notice: The grip frame modification is a permanent alteration to the factory Glock 43X MOS and may void the Glock factory warranty. However, all Shield Arms components—including S10 magazines and the magwell system—are covered by our 100% lifetime warranty. Once modified, the frame cannot be restored to OEM configuration.
Firearm Transfer Requirements: As a complete firearm, this product must be transferred through a Federal Firearms License (FFL) dealer. You will need to provide your FFL dealer's information during checkout. We handle all coordination with your dealer to ensure a smooth transfer process.
Custom Package Configurations
Enhanced Package
The foundation package includes everything you need for immediate deployment: Custom S10 Series Glock 43X MOS with precision-modified frame, two S10 10-round magazines, and black nitride standard steel magazine catch. Perfect for those who prefer to customize sights and accessories on their own terms.
Pro-Carry Package
Elevates the Enhanced Package with upgraded AmeriGlo I-Dot night sights for low-light capability. The I-Dot configuration provides fast sight acquisition with a single tritium dot front sight and blacked-out rear, ideal for defensive scenarios where speed matters most.
Elite-Carry Package
The ultimate Custom S10 configuration combines all Pro-Carry features with a black nitride threaded barrel for suppressor compatibility and a McNally trigger upgrade for enhanced shooting performance. This is the premier choice for serious concealed carry professionals seeking maximum capability in a minimal package.
Custom Cerakote Finish Options
Every Custom S10 Series pistol is Cerakoted in-house by Shield Arms craftsmen, ensuring superior durability and corrosion resistance. Choose from our curated finish selection:
- Black (Standard) - Classic nDLC factory finish for traditional appearance
- Fallout - Multi-tone tactical pattern with urban aesthetic
- Montana Mud - Earth-tone camouflage perfect for outdoor carry
- Pineland - Green-dominant pattern for woodland environments
All Cerakote finishes provide exceptional wear resistance and protection against the elements, while giving your Custom S10 a truly distinctive appearance. Each application is carefully executed to ensure even coverage and lasting beauty.
About the Glock 43X MOS Platform
The factory Glock 43X MOS serves as the foundation for the Custom S10 Series, and for good reason. Chambered in 9x19mm, this pistol represents Glock's refined approach to the concealed carry market. The MOS (Modular Optic System) slide features precision-milled cuts that accept micro red dot optics without the need for adapter plates, providing a lower mounting position and better co-witness with iron sights.
Glock's Slimline series design philosophy shines through in every aspect of the 43X MOS. The subcompact slide length paired with a compact-length grip creates ideal balance and handling characteristics, while the slim 1.1-inch width ensures comfortable concealment for all body types. The match-grade Glock Marksman Barrel delivers Gen5-level accuracy, and precision-milled front serrations provide positive slide manipulation even with wet or gloved hands.
Additional Slimline features include a short trigger distance for improved control, an integrated beavertail frame design for high hand placement, and the tough nDLC slide finish that resists wear and corrosion. The Glock Slim Mounting Rail accommodates compact weapon lights, making the 43X MOS a serious defensive tool before Shield Arms ever touches it.
Made in USA with Lifetime Warranty
Every Custom S10 Series Glock 43X MOS is modified and assembled in the United States by Shield Arms technicians. All Shield Arms components—including S10 magazines, the magwell system, and the steel magazine catch—are covered by our industry-leading 100% lifetime warranty. The included S10 magazines also feature our exclusive "Spring for Life" guarantee, ensuring they'll serve you reliably for years to come.
Technical Specifications
| Specification |
Details |
| Base Platform |
Factory Glock 43X MOS |
| Caliber |
9x19mm (9mm Luger) |
| Magazine Capacity |
10 rounds (flush-fit S10), compatible with 15-round S15 |
| Included Magazines |
Two (2) S10 10-round magazines |
| Barrel Length |
3.41 inches (standard), threaded barrel option available |
| Overall Length |
6.50 inches |
| Width |
1.10 inches |
| Slide Finish |
nDLC (factory) or custom Cerakote options |
| Optics Ready |
Yes - MOS slide cuts for micro optics |
| Rail System |
Glock Slim Mounting Rail |
| Trigger |
Factory Glock Safe Action (McNally upgrade available) |
| Sights |
Factory Glock sights (AmeriGlo I-Dot upgrade available) |
| Magazine Catch |
Black nitride standard steel (Shield Arms) |
| Magwell System |
S10 magwell (Shield Arms) |
| Build Time |
12-14 business days (custom build-to-order) |
| Warranty |
Shield Arms lifetime warranty on all modified components |
| Country of Origin |
Modified and assembled in USA |
Comparison: Custom S10 vs. Factory Glock 43X
| Feature |
Custom S10 Series |
Factory Glock 43X |
| Magazine Capacity |
10 rounds flush-fit (S10) or 15 rounds (S15 compatible) |
10 rounds with protruding baseplate |
| Magazine Profile |
True flush-fit with grip frame |
Extended baseplate profile |
| Magazine Catch |
Steel construction for durability |
Polymer (factory) |
| Magwell System |
Purpose-built S10 magwell installed |
No magwell |
| Concealment Profile |
Optimized for deep concealment |
Standard concealment profile |
| Customization |
Multiple package and finish options |
Factory configuration only |
| S15 Compatibility |
Full compatibility with S15 magazines |
Requires aftermarket mag catch |
| Test-Fired |
Yes - every pistol |
Factory test-fired |
Frequently Asked Questions
What makes the Custom S10 different from a standard Glock 43X MOS?
The Custom S10 Series features precision CNC machining to modify the grip frame for flush-fitting S10 magazines. We install a custom S10 magwell system and steel magazine catch, creating a true flush-fit 10-round capacity. The factory Glock 43X uses magazines with protruding baseplates and cannot accept S10 or S15 magazines without modification.
Can I use S15 magazines in the Custom S10?
Yes! The Custom S10 Series is fully compatible with the entire S15 product line, including S15 magazines and extensions. The installed steel mag catch and magwell system work seamlessly with both S10 and S15 magazines, giving you flexibility between flush-fit 10-round capacity and extended 15-round capacity.
How long does it take to receive my Custom S10 pistol?
Due to the custom build-to-order nature and FFL transfer process, Custom S10 Series pistols typically ship within 1-2 weeks from order placement. Each pistol is individually built to your specifications, test-fired for reliability, and then shipped to your designated FFL dealer.
Is the frame modification reversible?
No, the grip frame modification is permanent and cannot be restored to factory Glock configuration. This modification may void the Glock factory warranty. However, all Shield Arms components including the S10 magazines and magwell system are covered by our lifetime warranty.
What's included with the Enhanced Package?
The Enhanced Package includes the Custom S10 Series Glock 43X MOS with modified frame, two S10 10-round magazines, and a black nitride standard steel magazine catch. This is the base configuration, and you can upgrade to Pro-Carry or Elite-Carry packages for additional features.
Can I add a threaded barrel later if I choose Enhanced or Pro-Carry?
Yes, threaded barrels can be added later, though purchasing the Elite-Carry Package provides the best value if you know you'll want suppressor capability. The threaded barrel included in the Elite-Carry Package is professionally fitted and test-fired with your specific pistol.
What is the difference between the Cerakote finish options?
All Cerakote finishes provide superior wear and corrosion resistance. Black maintains the classic appearance similar to factory nDLC. Fallout offers a multi-tone tactical pattern, Montana Mud provides earth-tone camouflage, and Pineland features a green-dominant woodland pattern. All finishes are applied in-house for consistent quality.
Do I need to provide my FFL information?
Yes, as this is a complete firearm, it must be transferred through a Federal Firearms License (FFL) dealer. During checkout, you'll provide your chosen FFL dealer's information. We coordinate directly with your dealer to ensure a smooth transfer process.
Are S10 magazines legal in restricted states?
The S10 magazine has a 10-round capacity, making it compliant in states with 10-round magazine restrictions. However, you are responsible for understanding and complying with all federal, state, and local laws regarding firearms and magazine capacity in your jurisdiction.
What is the "Spring for Life" guarantee?
Our exclusive Spring for Life guarantee means if your S10 magazine spring ever wears out or fails, we'll replace it free of charge for the life of the magazine. This is in addition to our standard lifetime warranty covering manufacturing defects and material failures.
Can I install my own optic on the MOS slide?
Yes, the Glock 43X MOS slide features precision-milled optics cuts compatible with popular micro red dot sights. The MOS system allows direct mounting without adapter plates for a lower, more secure mounting position. Installation is straightforward for those comfortable working on firearms.
What if I have issues with my Custom S10 after delivery?
All Shield Arms components are covered by our lifetime warranty. If you experience any issues with the modified frame, magwell system, steel mag catch, or included S10 magazines, contact our customer service team immediately. We stand behind every Custom S10 Series pistol we build.
Who Should Buy the Custom S10 Series?
- Deep Concealment Carriers - Those who require the absolute lowest profile for appendix carry, ankle carry, or pocket carry while maintaining maximum capacity
- Professional Concealed Carriers - Law enforcement officers, federal agents, and security professionals needing a true backup or off-duty weapon with no printing
- Warm Weather Carriers - Individuals who carry with minimal clothing and need a pistol that disappears under light garments
- Glock Enthusiasts - Shooters who love the Glock platform but want enhanced capacity and concealment features not available from the factory
- Concealed Carry Permit Holders - Licensed carriers seeking the perfect balance between firepower and concealability for everyday carry
- Competitive Shooters - Those competing in carry optics or production divisions who want Glock reliability with enhanced capacity options
- Custom Firearm Collectors - Enthusiasts who appreciate precision-modified firearms with unique Cerakote finishes and enhanced features
- Serious Defensive Shooters - Anyone who views their carry pistol as a critical tool and demands the best available modifications and components
Related Products and Accessories
The Custom S10 Series Glock 43X MOS represents the ultimate evolution of Glock's concealed carry platform. With precision modifications by Shield Arms, you get factory Glock reliability enhanced with flush-fit capacity and complete S15 ecosystem compatibility—all backed by our lifetime warranty and made in the USA.
