
Availability: In Stock
The Warne MESW54BLK is a 6061-T6 aluminum magazine extension built specifically for Smith & Wesson M&P 9mm and .40 S&W platforms. If you're running a duty or carry gun and want a few extra rounds on board without committing to a full-capacity mag, this is a straightforward bolt-on solution. The extension adds 5 rounds to a 9mm magazine or 4 rounds to a .40 magazine, giving your reload a little more runway downrange or at the range. It's made in the USA and finished with Type 2 hardcoat anodize, so it'll hold up to regular holstering and abuse.
Warne engineered these extensions with practical use in mind. The ergonomic shape makes insertion smoother and less fumbling, and the finger grooves give you a positive grip when you need to peel the mag free from the gun. Retention is handled by a Torx head screw and washer—solid, tool-accessible hardware that won't rattle loose. The hardcoat anodize isn't just cosmetic; it protects the aluminum from corrosion and scuff marks that come with everyday carry and range work.
Whether you're working a duty gun in a restrictive jurisdiction, prepping a competition rig, or just want a modest capacity bump without swapping to an aftermarket magazine platform entirely, this extension bridges that gap. It's a clean, American-made answer to magazine capacity limitations.
| Brand | Warne Scope Mounts |
| Model | MESW54BLK |
| Material | 6061-T6 Aluminum |
| Finish | Type 2 Hardcoat Anodize |
| Fits | Smith & Wesson M&P 9mm / .40 S&W |
| Capacity Increase (9mm) | 5 rounds |
| Capacity Increase (.40 S&W) | 4 rounds |
| Fastener | Torx Head Screw & Washer |
| Country of Origin | USA |
Yes, the Warne MESW54BLK is designed for S&W M&P 9mm and .40 S&W platforms. It installs via a Torx head screw and washer, and adds 5 rounds for 9mm or 4 rounds for .40 S&W to a standard mag.
The extension is secured with a Torx head screw and washer. You'll need a Torx driver to install it, and it's a straightforward process that requires removing the original magazine basepad and attaching the extension in its place.
Yes. The extension is machined from 6061-T6 aluminum billet and finished with Type 2 hardcoat anodize, which resists scuffs, dings, and corrosion from holstering and daily carry. It's built to take the wear.
This extension adds rounds to an existing magazine. Magazine capacity laws vary by jurisdiction, so confirm your local regulations before purchasing or installing any capacity-increasing accessory.



SKU: 115666480 • Width: 3.1in • Height: 1.2in • Depth: 12.6in • Weight: 0.19oz





Availability: In Stock
The Warne MESW54BLK is a 6061-T6 aluminum magazine extension built specifically for Smith & Wesson M&P 9mm and .40 S&W platforms. If you're running a duty or carry gun and want a few extra rounds on board without committing to a full-capacity mag, this is a straightforward bolt-on solution. The extension adds 5 rounds to a 9mm magazine or 4 rounds to a .40 magazine, giving your reload a little more runway downrange or at the range. It's made in the USA and finished with Type 2 hardcoat anodize, so it'll hold up to regular holstering and abuse.
Warne engineered these extensions with practical use in mind. The ergonomic shape makes insertion smoother and less fumbling, and the finger grooves give you a positive grip when you need to peel the mag free from the gun. Retention is handled by a Torx head screw and washer—solid, tool-accessible hardware that won't rattle loose. The hardcoat anodize isn't just cosmetic; it protects the aluminum from corrosion and scuff marks that come with everyday carry and range work.
Whether you're working a duty gun in a restrictive jurisdiction, prepping a competition rig, or just want a modest capacity bump without swapping to an aftermarket magazine platform entirely, this extension bridges that gap. It's a clean, American-made answer to magazine capacity limitations.
| Brand | Warne Scope Mounts |
| Model | MESW54BLK |
| Material | 6061-T6 Aluminum |
| Finish | Type 2 Hardcoat Anodize |
| Fits | Smith & Wesson M&P 9mm / .40 S&W |
| Capacity Increase (9mm) | 5 rounds |
| Capacity Increase (.40 S&W) | 4 rounds |
| Fastener | Torx Head Screw & Washer |
| Country of Origin | USA |
Yes, the Warne MESW54BLK is designed for S&W M&P 9mm and .40 S&W platforms. It installs via a Torx head screw and washer, and adds 5 rounds for 9mm or 4 rounds for .40 S&W to a standard mag.
The extension is secured with a Torx head screw and washer. You'll need a Torx driver to install it, and it's a straightforward process that requires removing the original magazine basepad and attaching the extension in its place.
Yes. The extension is machined from 6061-T6 aluminum billet and finished with Type 2 hardcoat anodize, which resists scuffs, dings, and corrosion from holstering and daily carry. It's built to take the wear.
This extension adds rounds to an existing magazine. Magazine capacity laws vary by jurisdiction, so confirm your local regulations before purchasing or installing any capacity-increasing accessory.
SKU: 115666480 • Width: 3.1in • Height: 1.2in • Depth: 12.6in • Weight: 0.19oz


