CAP GAP extension question

[AjayB]

I have found the below answer for my cap gap extension, what i dont understand from the below answer is " what does it mean by Fedex reciept?

How does a student covered under the cap gap extension obtain proof of continuing status?

The student should go to their Designated School Officer (DSO) with evidence of a timely filed H-1B petition (indicating a request for change of status rather than for consular processing), such as a copy of the petition and a FedEx, UPS, or USPS Express/certified mail receipt. The student’s DSO will issue a preliminary cap gap I-20 showing an extension until June 1st. If the student’s petitioning employer receives a notice of selection from USCIS, the student should return to his or her DSO with a copy of the receipt notice, if possible, for issuance of a new cap gap I-20 indicating the continued extension of status.

Students can also check the Student and Exchange Visitor Program information from the Related Links section of this page.

http://www.uscis.gov/portal/site/uscis/menuitem.5af9bb95919f35e66f614176543f6d1a/?vgnextoid=7f1a046c43360210VgnVCM1000004718190aRCRD&vgnextchannel=68439c7755cb9010VgnVCM10000045f3d6a1RCRD

[IM129]

"such as a copy of the petition and a FedEx, UPS, or USPS Express/certified mail receipt"

You need to carry the H1B filing copy and also proof that you(your employer) have filed it IN-TIME, the FEDEX Reciept means..certified recipt(tracking recipt label) from the fedex delivery to the USCIS centre applicable

[IM129]

"such as a copy of the petition and a FedEx, UPS, or USPS Express/certified mail receipt"

You need to carry the H1B filing copy and also proof that you(your employer) have filed it IN-TIME, the FEDEX Reciept means..certified recipt(tracking recipt label) from the fedex delivery to the USCIS centre applicable