When doing ring flight you can use whatever you like a case or no case. However many put down the key case BUT it is still readily sold and used.

Just do a google search.

Here is one that is on the deluxe side and currently available,they are used to keep keys from tearing pockets and add a little class.

http://www.davidmorgan.com/popup_image.p......1&tab5=1

Look for JUST-IN-CASE at http://joeporper.net/product/just-in-case/