What does this statement mean?

HI!

I was recently reading an article about McDermott International, Inc., and I came across a sentence I'm not exactly sure about....

Here it is:

"The amended agreement replaces the prior borrowing capacity of $450 million and provides McDermott with $810 million capacity of letters along with $300 million revolving cash sublimit." (Investopedia, 2017).

Can someone help explain this statement to me? Particularly, the "capacity of letters" and "revolving cash sublimit" part?

Thanks a lot!

Submitted July 15, 2017 at 07:31PM by shahm5reddit http://ift.tt/2t2T60f