The term "Buff" itself is trademarked
I just checked on its history and apparently born in the year 1991

I have seen the contestants of the reality show Survivor who are always given "Buffs" to identify which tribe they are a part of

The Buff, this tubular bandana can be worn in a variety of styles and is made of a material that keeps you cool on a hot day, and warm on a cold day. And I believe it has no seam as well.

Mine is a copycat and with a seam ;p
And if you do needlework, the community is a good one to be part of ... very supportive and they have some pretty fancy ideas too ;D