Full length tactical rails look impressive on Remington 870 shotguns but they are very expensive. For example, Rhino rail is about $200, Mesa Tactical rail is 209.99.

Here is good and less expenisve alternative from Black Aces Tactical. It has rails where you can install holographic sight, flip-up sights, flashlight, laser, etc. And also works as a heatshield.

Shotgun Tactical Rails for Remington870

Shotgun Tactical Rails for Remington870

Features:

One piece T6 6061 aluminum construction
Lightweight at only 16 ounces (Mossberg model is 14)
Type 2 black anodizing
No gunsmithing required, fits tapped and untapped receivers
Serial numbers remain visible
Tools and instructions are included for installation
Allows for a variety of accessories to be mounted to your shotgun
Top Picatinny rail is 21” in length

ATTENTION: Will not work with barrells with rifle sights .

The price of Shotgun Tactical Rails for Remington 870 from Black Aces Tactical $139

Recommended Product:
Black Aces Tactical Rail

Black Aces Tactical Rail

 You can get Shotgun Tactical Rails for Remington 870 from Black Aces Tactical here: http://tinyurl.com/8mukfqs