G&G Armament have shared details of their ETU and MOSFET set for GR14:
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Elevate the performance of your M14 replica with our advanced Electronic Trigger Unit drop-in kit and upgraded MOSFET for enhanced trigger response. Compatible with Version 7 gearboxes, our GR14 ETU and MOSFET will fit all compatible G&G rifles as well as many other brand gearboxes. Now available worldwide
G&G Armament