FAB Defense AGR870-FKSB Remington 870 M4 Shock-Absorbing Collapsible Stock

FAB Defense AGR870-FKSB Remington 870 M4 Shock-Absorbing Collapsible Stock

The FAB Defense AGR870-FKSB is a recoil-reducing collapsible stock system designed for Remington 870 12-gauge shotguns. It combines an M4-style adjustable buttstock, integrated pistol grip, and a built-in shock-absorbing mechanism intended to reduce felt recoil while giving the shooter greater control over stock length and rear-end configuration.

Unlike a conventional fixed Remington 870 stock, the AGR870-FKSB allows the length of pull to be adjusted through multiple positions. This can be useful when adapting the shotgun to different shooters, clothing, body armor, or shooting positions. The shock-absorbing assembly is integrated into the stock system rather than relying only on a soft recoil pad.

Key Features

• Designed for Remington 870 12-gauge shotguns
• Integrated shock-absorbing stock system
• M4-style collapsible buttstock
• Multiple stock-length positions
• Integrated pistol grip
• Textured gripping surfaces
• Storage compartment in the pistol grip
• Rubberized buttpad
• Reinforced polymer construction
• Black finish

Shock-Absorbing Stock System

The defining feature of the AGR870-FKSB is its built-in recoil-management mechanism. Rather than functioning as a simple rigid adapter and collapsible stock, the system incorporates movement within the stock assembly to absorb part of the rearward recoil impulse before it reaches the shooter.

This design is intended to improve recoil management during repeated firing while preserving the adjustability of an M4-style stock. The pistol-grip geometry also provides a more vertical hand position than a traditional field stock and incorporates textured surfaces for a more secure grip.

Adjustable M4-Style Configuration

The collapsible stock provides multiple length-of-pull settings, allowing the rear of the shotgun to be adjusted to the shooter rather than requiring a single fixed stock length. This is particularly useful when transitioning between light clothing and bulkier equipment or when the shotgun is shared between users with different proportions.

Compatibility

• Manufacturer: FAB Defense
• Model: AGR870-FKSB
• Platform: Remington 870
• Gauge: 12 Gauge
• Type: Shock-Absorbing Collapsible Stock System
• Color: Black
• MPN: FX-AGR870FKSB
• UPC: 7290105940803

Fitment Note: This stock system is intended for Remington 870 12-gauge shotguns. Buyers should confirm their exact receiver configuration and existing aftermarket components before installation.

Designed Around the Remington 870

The AGR870-FKSB is not simply an AR-style stock adapted generically to a shotgun. FAB Defense designed the system around the Remington 870 receiver and combined the mounting interface, pistol grip, collapsible stock, and recoil-management assembly into a dedicated shotgun stock system. For buyers comparing it with a conventional M4-style conversion, the built-in shock absorber is the primary functional difference.

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