Original I-94 Or Copy, When Sending To Uscis?

[secaucus]

I read somewhere on this website that one should not send the original form I-94, even though the form I-539 (application to extend status) says to do so, when filing for an extension of stay on visitor b1/b2 visa, and that we should just send a copy of said form.

Is there a special reason for this?

Is it better for us to keep the original?

Could someone explain please?

Thanks!

[immihelp]

Send the copy only. You need to submit the original I-94 at the airport while leaving.