Ever put a piece of paper or book in your bag thinking it’ll be alright, as it’s only going to be in there for a little while? I couldn’t tell you how many papers, books and file folders have gone into my messenger bag this way and come out looking like they’ve been eaten.

Vinyl document envelopes (the byzantine, but most commonly used name for them) have been the answer to this problem for me. I first used one about a year and half ago to keep itineraries and travel plans safe while I was traveling through Europe. I’m glad I did, because otherwise my constant rummaging for my camera and jacket would’ve had disastrous effects.

I didn’t immediately make the jump to using one of these in my day-to-day life, but last fall after weeks of jostling around in my bag permanently disfigured my paperback copy of David Allen’s Getting Things Done, I decided to keep one in my bag at all times.

I found the envelope pictured above at Office Max for about $5. It’s nicer than most because it’s made of a thicker vinyl and has nylon fabric edges that allow it to expand out to three inches. You can buy smaller, cheaper, flimsier ones for $1-2. Make sure to get one with a flap that folds over to keep your stuff safe and sound inside.

They come in a variety of colors, but I suggest clear or opaque; that way maps, itineraries, to do lists and other frequently referenced materials can be kept in the front or back and seen quickly without having to open the envelope and pull things out.