I'm not sure what year I first used one. It had to be somewhere in the 70's when they were large and keeping a Coke cold longer was never a factor for me because I drank fast anyway.
Now days, I have Koozies in my kitchen, my golf bag, and every vehicle. I have plain Koozies. Koozies with advertisements on them.
Eugene's Pizza out of Glasgow, Briarwood, Ist Bank, The Powderhorn Lounge, Some random guys 50th B-day party, Junction City Saloon in Custer are all represented in my collection.
But my favorite is (Yes, I have a favorite koozie) A General Lee Koozie. Given to me by my friend, Jennifer Avants after a trip she took to Nashville.