Fostech Echo Sport Trigger Fast Fire Binary Trigger System For AR-15 Platform Rifles, Safe, Semi, and Echo Firing Modes - Model 4140

The Echo Sport from Fostech is a more economical version of their world-famous Echo II rapid-fire trigger system for the AR-15. It has all the functionality of the Echo II trigger with the only difference being that you select the Echo mode from a paddle located in front of the trigger, rather than through the use of the safety selector. The advantage of the Echo Sport trigger is that it provides the same binary (fire on pull and release)  trigger function as the original Echo II trigger, at a more affordable price. It is more efficient, less complex, and most importantly, less money than the Echo II. So what exactly are the differences between the Echo Sport Trigger and the Echo II?  Well, there is one primary difference. While the Echo Sport provides the same Echo Firing mode as the original Fostech Echo II Trigger, the controls have been modified to eliminate the use of the 3rd safety selector position. Instead of utilizing the safety selector to go to the third Echo Mode position.... as select-fire rifles would do...., a control paddle in front of the trigger guard moves side to side to select single fire or Echo firing modes. Therefore, with the exception of the firing mode selection method, you get the same highly sought-after Echo functionality, but at a significantly lower price!
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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 Echo Sport trigger is designed to work in direct impingement AR-15 platform firearms and works with any standard full-auto style bolt carrier group which are the BCGs that are utilized in virtually all current production ARs.  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 Sport trigger is fully approved by the ATF. 

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