The first time I saw a Buff was when my son attended the last National Boy Scout Jamboree at Fort A. P. Hill about ten years ago. I saw them in the registration tent, but did not pay much attention to them. Later standing in line at food tent, a Scout in line next to us had one, and kept playing around with different ways to wear them, and the usefulness became apparent.
Now days, summer or winter, I always carry one or two of them. It’s as easy as carrying along a couple of handkerchiefs.
In just a few seconds I can turn one into a neck gaiter, toboggan, balaclava, sweat band, or other function. I prefer the merino wool ones in preference to the microfiber ones, because I like merino wool, and the the merino wool versions are just a little longer than the microfiber models.
It’s amazing that in summer time if you hike to the top of a mountain were it’s much cooler than where you started, drop a buff around your neck and you feel five ~ 10˚ warmer even if all you’re wearing are shorts, a tee-shirt and shoes. After dropping 36# over the past eight months, I’ve lost a lot of inbuilt insulation and appreciate having a buff handy more than before.
But they also come in versions that block uv, or are supposed to repel insects. I also like the Polar Reversible models for winter, but they are to bulky to carry in your pocket, fleece on one side, normal material on the other side. Which is different from the Polar buff versions, which is a normal buff with a fleece extension.
http://www.buffwear.com/buff-adult-headwear/original-buff
It pays to look around at different Buff websites to find the model you want. I have found the site in the UK often carries different models, than the sites in the USA, and delivery time and cost are about the same. But the USA sites often have models the UK site does not have.