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Finish Your Lower Kit: FosTecH Echo Sport Binary Trigger for the AR-15 Platform + AR-15 Mil-Spec Buffer Tube Kit + KAK AR-15 "Lite" LPK + SB Tactical SBM4 Pistol Stabilizing Brace

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On sale $614.99 $379.99
Retail Price:$614.99
Your Savings:$235.00(38%)
Part Number: CO-83998
Availability: In Stock
Finish Your Lower Kit:
+ FosTecH Echo Sport Binary Trigger for the AR-15 Platform
+ Omega Mfg. AR-15 Heavy Duty Pistol Buffer Tube
+ KAK AR-15 "Lite" Lower Parts Kit
+ SB Tactical SBM4 Pistol Stabilizing Brace, For Pistol Tube

FosTecH Echo Sport Binary Trigger for the AR-15 Platform

Builders and Shooters know that the best upgrade you can do to your AR-15 is getting a reliable, smooth & light pull trigger. Thanks to the modularity of the AR-15 platform, upgrading your standard Mil-Spec Trigger with enhanced parts, or even a self contained all in one Drop-In trigger is as easy as punching out 2 pins from your lower receiver and ‘Dropping In’ your new upgrade. Binary triggers serve a special function of being able to increase the shooter's ability to shoot faster under a single action of the trigger. Binary triggers work by releasing the hammer when the trigger is pulled, and when the trigger is released. Binary Triggers are a great upgrade for standard AR-15 Rifles, and Pistol Caliber Carbines!

About this Trigger: The Fostech Echo Sport Trigger is more efficient, less complex, and most importantly LESS MONEY than other binary triggers. From an operational standpoint, the only difference the operator will notice is that the selector for the Echo operation is located inside the trigger well on a paddle. Move to the left for Echo Mode and move to the right for Semi-Automatic. The ECHO Sport is an economical pull and releases a trigger for the AR-15 platform. To explain how this trigger functions, every time you pull the trigger a bullet fires, and your BCG cycles a new round, when you release the trigger another bullet fires and your BCG then cycles another new round. This is not a machine gun, this is a single action for every round trigger which is the definition of semi-auto fire. One round per action on the trigger, once per pull, and once per release.

Compatibility: This trigger is designed to work with Mil-Spec AR-15 lower receivers and can be installed in just a few minutes!

Anti-Walk Pins: Not Included - This enhanced trigger is to be a direct replacement for your original trigger. Trigger pins are not included, but you can re-use the trigger pins from your standard lower parts kit.

Color: This trigger is Burnt Bronze accented.

Trigger Style: Standard M4 - This trigger uses a standard Mil-Spec curved trigger shoe.

Main Feature: Binary

Omega Mfg. Heavy Duty Pistol Buffer Tube

This Omega Mfg. AR-15 Pistol Buffer Tube is ready to install on your AR-15 pistol build. This buffer tube is machined to strict standards to provide an excellent fit and reliable function. The Omega Mfg. the buffer tube is machined from 6061-T6 aluminum and given a hard coat anodized finish to withstand years of abuse. The outside diameter of 1.248" is sized for SB Tactical Braces. Fabricated to be a superb product for pretty much anybody, we're sure you'll love the Omega Mfg. Pistol Buffer Tube.

Pistol Buffer Tube does fit SBM4 but will be a very tight fit.

Note: May or May Not Include Foam Pad, Snug fit for most Pistol Braces and/or Blades

AR-15 Carbine Castle Nut

Standard Mil-Spec Castle Nut

Mil-Spec Receiver End Plate

Maintains Proper Alignment of Stock & Buffer Tube

M4-style receiver plate includes the engagement tab required to align the buttstock and buffer tube with the lower receiver on carbine models.

Precision, fine blanking process ensures precise edges and superior flatness for correct fit and solid installation.


Phosphate Finish

Made of 4140 Hardened Steel

AR-15 Carbine Recoil Spring

Made of the finest spring steel rated for 20,000+ rounds

AR-15 Carbine Recoil Buffer


Weighs 3 oz.

Standard carbine length buffer

Aluminum 6061-T6 exterior

Fits AR-15 and M16 carbine buffer tubes

Use with standard AR-15/M16 carbine buffer springs


3 oz. weight allows for more reliable function in rifles with shorter gas systems

3 oz. weight reduces bolt bounce in full auto fire

Increased weight also softens recoil

Standard dwell time for normal cycling of the rifle

KAK AR-15 "Lite" Lower Parts Kit

General Info: Lower Parts Kits include all of the small bits & pieces needed to make your AR-15 Lower fully functional. Such as the mag release, take-down pins, selector, trigger guard, bolt catch, buffer retainer, roll-pins, detents, and small springs are included to allow completion. This KAK Lower Parts Kit contains all of the necessary pieces needed to complete your build EXCEPT the trigger and components that go along with them. You can find triggers & fire control groups (HERE [https://www.omegamanufacturinginc.com/gun-triggers.html])

Brand: The 'Lite' Lower Parts Kit is produced by KAK Industries [https://www.omegamanufacturinginc.com/kak-industries-ar-products.html] with high-quality steel & brass components.

Brand Info: KAK Industry was founded and incorporated in 2011 by Kurt Kosman to address a gap in the firearms market for quality, American-Made components at affordable, sustainable prices. KAK began in one small shop, supplying specialty firearms components with innovative designs to shooters and hunters across America. Almost immediately, the demand for these products grew to such that a dedicated manufacturing facility was opened in Southern California, a major aerospace manufacturing hub.

Platform: Commercial AR-15

FCG Included: The 'Lite' Lower Parts Kit does NOT come with a hammer, hammer spring, trigger, trigger spring, disconnector, disconnector spring, or hammer & trigger pins. This kit is for completing your AR-15 lower and allowing an affordable parts kit in the case you already have drop-in triggers on-hand and ready to install.

Weight: The overall weight of the 'Lite' Lower Parts Kit is 0.335lbs.

SB Tactical SBM4 Pistol Stabilizing Brace, For Pistol Tube

General Info: Fixed Pistol braces are a great and cost-effective solution to AR pistol builds. Fixed Pistol Braces are simple in design and easy to install, featuring a minor level of adjustability and sleek design, that saves weight and demonstrates great stabilizing properties. Fixed Pistol braces are the ideal & affordable solution for your next AR pistol build.

Brand: SB Tactical - As the originator of the forearm Pistol Stabilizing Brace®, SB Tactical® is a groundbreaking thought leader committed to providing hard-core shooters what they need. In an industry reluctant to challenge conventional wisdom, we transformed the possibilities of large frame pistols. We will stop at nothing to help our customers overcome challenges with brilliantly engineered, expertly constructed solutions.

Model: SBM4 Pistol Stabilizing Brace

Weight: This brace features an overall weight of 0.40 lbs.

Platform: AR-15

Buffer Tube Compatibility - Pistol Buffer Tube: The SBM4 Pistol Stabilizing Brace is held securely onto the pistol by press-fitting tightly on a pistol buffer.

Material: SBM4 Pistol Stabilizing Brace Is made out of Reinforced Polymer and Flexible Rubber for reliability and impact resistance against the great outdoors.

To view the most up-to-date shipping times Click HERE.
To view Warranty, Returns, Terms & Restrictions Click HERE.

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