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Questions & Answers
In the specs it says 10 inches. This would put it out past the muzzle on an m4 carbine. I have seen other posts say it is 6.5 inches. Wich is it? Expert Answer

According to the manufacturer the Ergo Grip AR-15 M4 Forward Rails for Front Sight Base is 10" long.

by Hunter, Gear Expert, July 21, 2022
Will this fit on a colt M4 Monolithic? Expert Answer

The Ergo Grip AR-15 M4 Forward Rail fits any AR15 pattern rifle that uses a fixed front sight. As long as you have a fixed front sight, this rail will be compatible as it uses the front sight block to install.

by Ethan, Gear Expert, October 5, 2023
Customer Reviews
Helpful Positive Review
Not as advertised by PNWGuy, August 27, 2022
The photo of this item on the website shows that the rail has white T Marks- the item I received did not have any T Marks at all. The rail still works as intended but what is shipped is not the same item as depicted in the photo.
3/3 found this helpful
Helpful Positive Review
ergo m4 quad rail extension by Red fox, December 16, 2015
Used this on a colt 6940 monolithic upper as a rail extension. Had to machine it some to fit but worked great. Rock solid but a little on the heavy side. Also the product I recieved didn't have the white lettering as seen in the example photo. No bi...
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1/1 found this helpful
Helpful Positive Review
Excellent product as advertised. Installation was quick and easy and it is solid. Installation on my rig allowed attachment of an angled fore grip more proximal to the business end of the barrel. The only issue I found is that the product really cond...
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2/2 found this helpful
Helpful Positive Review
Ergo grip ar 15 by Joe, January 31, 2020
Works really well for its intended use of giving you more room on your rifle for mounting and extra support hand length. The only down side would be the nuts that hold it in place come loose after shooting and banging against barricades.
1/1 found this helpful
Helpful Positive Review
Major improvement by Recon, March 4, 2016
I got this rail system because I didn't want to spend the money on a Troy industries extended rail. Well I could afford it but didn't was looking at other options. I went with the Ergo grip because it allows to grab the rifle more closer to barrel to...
Read More...
2/3 found this helpful
Most Recent Reviews
Not satisfied with the quality of the finish by Brendan, Verified Owner, May 2, 2024
This rail extension is a cool idea and a cost effective way of adding more rail space on a FSB platform but the finish quality of the product I received was sub par. Parts of this quad rail extension arrived in the mail scratched up and rusty. This i...
Read More...
Read All 12 Reviews
Color: Black Finish: Anodized Fabric/Material: 6061-T6 Aluminum Gun Rail: Picatinny Gun Make: AR Platform Gun Model: AR-15 , M4 , M16 Length: 10 inWeight: 8.7 ozIncluded Accessories: LowPro Rail Covers Condition: New Quantity: 1

Code: 3E-T8-ERFRAR15SB-4850

MPN: 4850

UPC: 874748004442

Final Sale
List: $99.99Save $4.00
$95.99

Product Info for Ergo Grip AR-15 M4 Forward Rails for Front Sight Base

The Ergo Grips M4 Forward Rail is a stand-alone rail system for AR/M4 weapons with a standard A1/A2 front sight base. Installs onto A1/A2 front sight base, locking inside the front sight and requiring no modification to your firearm. The Ergo M4 Forward Rail allows for attachment of Picatinny rail mounted accessories forward of the front sight base. It will not take up all your space and allows you to mount multiple accessories. The Ergo M4 Rail also provides extended hand hold opportunities for shooters. Included is an ERGO LowPro rail cover as well. Don't dawdle any longer; get yours now!image

WARNING: California`s Proposition 65

Specifications for Ergo Grip AR-15 M4 Forward Rails for Front Sight Base:

Manufacturer: ERGO
Color: Black
Finish: Anodized
Fabric/Material: 6061-T6 Aluminum
Gun Rail: Picatinny
Gun Type: Rifle
Gun Make: AR Platform
Gun Model: M16, M4, AR-15
Length: 10 in
Weight: 8.7 oz
Included Accessories: LowPro Rail Covers
Condition: New
Quantity: 1
Last Chance: Yes

Features of Ergo Grips AR Forward Picatinny Rail:

  • Allows for attachment of Picatinny rail mounted accessories forward of the front sight base
  • Provides extended hand hold opportunities for shooters with Ergo LowPro rail covers for comfort
  • Installs onto A1/A2 front sight base, locking inside the front sight - requiring NO modification to firearm

Package Contents:

  • Ergo Grip AR-15 M4 Forward Rails for Front Sight Base
  • Installation hardware and 2 black picatinny rail covers.

Ergo Grip AR-15 M4 Forward Rails for Front Sight Base Orderable Models

List of Orderable Models

  • ERGO Grip AR-15 M4 Forward Rail f/Front Sight Base, 4850 , MPN: 4850 , UPC: 874748004442 , Code: 3E-T8-ERFRAR15SB-4850

Ergo Grip AR-15 M4 Forward Rails for Front Sight Base Unavailable & Discontinued Models

List of Unorderable Models

  • USED ERGO Grip AR-15 M4 Forward Rail f/Front Sight Base, 4850, EDEMO9, Condition Fair, Installed/Mounted , MPN: 4850-EDEMO9 , Code: 3E-T8-ERFRAR15SB-4850-EDEMO-IN-D
  • USED ERGO Grip AR-15 M4 Forward Rail f/Front Sight Base, 4850, EDEMO8, Used, Condition Fair , MPN: 4850-EDEMO8 , Code: 3E-T8-ERFRAR15SB-4850-EDEMO8
  • USED ERGO Grip AR-15 M4 Forward Rail f/Front Sight Base, 4850, EDEMO7, Used, Condition Like New , MPN: 4850-EDEMO7 , Code: 3E-T8-ERFRAR15SB-4850-EDEMO7
  • USED ERGO Grip AR-15 M4 Forward Rail f/Front Sight Base, 4850, EDEMO6, Used, Condition Fair , MPN: 4850-EDEMO6 , Code: 3E-T8-ERFRAR15SB-4850-EDEMO6
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