A Question Concerning Mint/Proof Envelopes

Awesome find, thanks...I put my order in this morning. My wife is not taking to all my acquisitions sitting in piles on the bookshelf. This should alleviate the problem.

I ordered some of those bags, though I did not like them. The plastic was loose and seemed to get in the way when stacking these. I recently made an order on ebay, and one of the envelopes came wrapped in (what I thought to be) a really cool plastic envelope. The plastic was stiffer (more like the plastic electronics come in) and had a tape sealed opening. I ordered two different sizes to fit the larger mint envelopes from the late 70's/early 80's. I ended up asking the guy what he used and he referred me to this site: http://www.davescollectiblecoins.com/storage-bags/