What type of usps delivery uscis will use?

[xtivater]

Is it a normal mail or we have to sign it to get it?
Thanks for your help !

[immihelp]

Delivery of what?

[xtian]

I've never had to sign for any immig. mail, they should do that to make sure people get it insted of scam people out of their hard earned money and on top of everything deny your case because you didn't received anything.

[xtivater]

Sorry admin if I didn't state it clearly.
What i mean is what kind of delivery type USCIS used to mail all those important documents including the receipt, the appointment letter, and even the green card.

So far, i think they use the delivery that doesn't require receiver's signature which is a little bit strange (if we put the amount of money we paid, the importance of such documents and in some cases, the time sensitivity.) I experienced some thick packages mailed to my address within the past few years (person with similar names or similar street names.)

I do not doubt the credibility of USPS (i used usps to send out my application forms).
I just wonder why USCIS doesn't require signature upon delivery of such important documents. I mean, I am willing to pay extra money to USCIS if I have that option (options like signature upon delivery, next day air, mail with tracking number...)

Thanks immihelp and xtian for your replies.