Echo1USA Tech Videos - M4 Gearbox Assembly

http://tiny.cc/rskdux Save 70% on any soft at M4gear
http://www.echo1usa.com Now that you've learned how to take down your Echo1USA M4 Gearbox let Brian, the Echo1 Tech, show you how to put it back together. In this video, Brian shows you how to put back that gearbox back together from start to finish. Remember to check out Brian's shenanigans at twitter.com/BRIANatECHO1.