Mesa Tactical SaddleRail 4 MOS – Mossberg 500/590 12 Gauge

The Mesa Tactical SaddleRail 4 MOS is a Picatinny rail mount designed for Mossberg 500 and 590 series 12-gauge shotguns. This saddle mount replaces the factory receiver cover, providing a stable, repeatable optics platform for red dots, holographic sights, or backup iron sights. The SaddleRail solves the common problem of shotgun receiver flex by securely clamping to both sides of the receiver, maintaining zero even under heavy recoil.

Machined from 6061-T6 aluminum with a matte black hard-anodized finish, the SaddleRail features four Picatinny slots for mounting flexibility. Installation requires basic hand tools and minor fitting—the rail clamps around the receiver using provided hardware, but proper alignment is critical for reliable function. Some users may need to lightly file the interior fit depending on receiver tolerances. This is not a drop-in part; take your time during installation or consult a gunsmith if unfamiliar with shotgun modifications.

• Part Type: Receiver Rail Mount
• Compatible Firearms: Mossberg 500/590 Series 12 Gauge
• Material: 6061-T6 Aluminum
• Finish: Matte Black Hard Anodized
• Rail Slots: 4-Slot Picatinny
• Installation: Requires Fitting and Proper Alignment
• Includes: Mounting Hardware