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Everything To Know About Binary Triggers
Everything To Know About Binary Triggers
25:36 | 4 years ago

Fostech Echo-II Drop In Trigger For AR-15 Platform Rifles - Gen II - Patented Fast Fire Trigger System by Fostech... ATF Approved

MPN: 4150  |  UPC: 639266300021
$399 99

In Stock


The Fostech Echo II AR Trigger is a revolutionary new fast fire trigger system with a groundbreaking drop-in design. It is not select fire, but like firearms with select-fire capabilities, the mode of fire is determined by the position of the safety selector. The 3 position safety switch on the Echo II trigger allows the shooter to choose between safe, semi-auto, and Echo ( fire on pull and release ) firing options.
The Echo mode option provides a greatly reduced gap time between rounds resulting in tighter follow-up shot placement. It is also a ton of fun.
The Gen II Echo Trigger is designed for direct impingement AR-15 rifles and works with any standard full-auto style bolt carrier group which virtually all AR-Platform rifles and pistols currently come with.
It provides a clean, crisp trigger pull regardless of the firing mode selected and the trigger pull in semi-auto mode is as good as, if not better, than most other standard mil-spec triggers. The Echo II trigger is fully approved by the ATF. 

For More Complete Information click on the SHOW MORE + tab below. 

The Echo Trigger allows the shooter to select from 3 different settings:

Safe Mode: Firearm will not fire. Semi-Auto Mode: Firearm fires when the trigger is pulled.  Echo Mode: Firearm fires when the trigger is pulled and also when the trigger is released.

The Echo Trigger is designed with safety being the utmost priority. Even in the Echo Mode if the shooter depresses the trigger firing one round, and decides not to fire the second, the shooter can move the selector to the safe position and a second round will not fire upon release. In addition, the Echo II trigger has several distinct features making it unique to the marketplace and its drop-in design makes it highly sought after by both recreational and professional shooters. The Echo II is packed full of cutting-edge technology and fires reliably in both the Semi-Auto and Echo Mode options. 

Summary of the Fostech Echo II trigger:

PATENTED Design that gained ATF Approval (Patent # US 8,820,211 B1)   
Light, clean, and crisp pull in Semi-Automatic Mode
Trigger Shape - Traditional Curved
Trigger Pull Weight - Range 4.5 - 5 lb


The Echo Trigger is designed to work with direct impingement AR-15 rifles and pistols. This is the Gen II variation which is the latest and most advanced version of the Fostech Echo triggers. The original Echo required a separate bolt to function but this Gen II trigger will work in any direct impingement AR-15 rifle utilizing a full auto bolt carrier which virtually all AR's are currently being produced with. Not sure if you have a semi or full auto bolt Click this link for further details.

The Echo II trigger provides for ultra-reliable function in both the standard Semi-Auto position and the Echo Mode, see videos and reviews...these things are awesome.

Note - Because of State laws, The Echo Trigger cannot ship to California, the District of Columbia, Iowa, New Jersey, New York, Hawaii, Rhode Island, Flordia, Maryland, Connecticut, Washington, Oregon, Massachusetts.




The evcho trigger has several distinct features:

  • PATENTED Design that gained ATF Approval (Patent # US 8,820,211 B1)
  • PATENTED Technology licensed through Franklin Armory inside the Echo AR-II Trigger, including U.S. Pat. Nos. 9,952,012 and 9,952,013
  • Light, clean, and crisp pull in Semi-Automatic Mode
  • Trigger Shape - Traditional Curved
  • Trigger Pull Weight - Range 4.5 - 5 lb
  • The Echo Trigger is packed full of cutting edge technology
  • Reliable function in Echo Mode
Country of Manufacture United States
License Requirement None
Manufacturer Fostech
Mfg. Part Number 4150
UPC 639266300021
Caliber/Gauge .223 / 5.56
Action No
Barrel Length No
Barrel Twist No
Barrel Bore Type No
Barrel Finish No
Barrel Fluting No
Barrel Profile No
Mount Type No
Beam Color No
Firearm Fit AR-15
Threaded Barrel No
Condition New
Free Shipping No

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