Richie, I think what you picked up are the screens one puts in the bottom of certain types of pipes to smoke that there wackie tobackie (and having gone to college in the late 60's, I've heard of such things!). What Bruce and Alan are referring to are are pipe wind screens, thin, round sheets of metal with many little holes punched them, (more solid than a disc of window screening) and two small raised "ears" that are spring loaded to hold it on the top of the pipe. My experience is they work OK, but not great.
I backpack and canoe camp a lot, used to be a back country guide at several National Parks and have smoked thousands of bowls in the back country or paddling. Unless you're being active while smoking, such as hiking (which is probably a bad idea to smoke then anyway), fly fishing (which unless it's really windy and you're near shore, shouldn't be too much of a problem without a wind screen), of paddling a canoe (which I do a lot), I never find a screen necessary. The one exception is a situation like I encountered in Glacier back country last summer. High fire danger, so the rangers didn't want to see a any lit anything. One caught me, sitting on a rock in the middle of the Belly River (at least 20' from either shore) with my pipe and the wind screen on it, laughed, and said if he didn't have to get his feet wet to get to me, he would have given me a ticket. But he walked away chuckling, so I doubt he would have.
My experience is my pipe is my best friend around the fire in the morning with coffee and sunrise, or at dusk watching the sun set with a splash of bourbon or a hot toddy. If I smoke a bowl during the day, I find a peaceful place out of the wind, sit and smoke, and put the pipe out before moving on. But then, I don't generally smoke when I'm moving around or doing physical work. So I don't really feel the need for a wind screen.
I do have, however, two different types of pipes that seem to work epically well in the woods. One is a pair of cheap Santos pipes I got on eBay, and both have the snap top metal lids that allow smoking with the lid down. The bent one hangs perfectly in my mouth when my hands are busy paddling through some riffs and smaller rapids, and the straight one is perfect for my day pack or backpack. However, 90% of what I use the lid for is to load the pipe in the morning, snap the lid down, and it's ready to go when ever I want, no tobacco falling out all over the pack. If I only smoke half the bowl, I wait until it goes out, wad up a corner of a tissue, stuff it over the top, snap the lid shut, and I've never had ash leak out when carried that way.
But my best traveling pipe is a Kirsten stem, (I like the large straight Lancer model) and two or three custom made bowls by Mike Brissitt that fit perfectly in these little Tupperware containers I have (the hight of a shot glass but a bit wider with tight fitting snap lids). I can load them in the morning and seal them in the containers, screw them on the stem to smoke when I want, put them back into the containers when done, and they're so convenient and light. If I ever figure out how to post pictures you'll see how efficient they are for both weight and size. Also, because the bowls screw off and their is no tenon to hold moisture, I find the bowls dry out much faster than standard pipes do, so they can be used more frequently.
Last summer we had a ten day back country permit in Glacier to do Stoney Indian Pass. My Kirsten pipe body, three different bowls and their containers, lighter, pipe cleaners, and seven different baggies of tobacco weighed just under 7 ounces. That's three good size bowls a day for ten days, and all together is was just about the size of a 16 oz beer can.
Sorry to be so verbose, but puffin my pipe in the woods is basically what I live for.
ipe:
Natch