Coffee sleeve. Mug hugger. Paper zarf. Coffee cozy/coozie. Even if you don’t recognize it by name, this handy accessory to the takeout cup of coffee is ubiquitous as it is functional.
It is meant to assist in insulating both hot and cold drinks in disposable or reusable cups and keep them at the optimum temperature while you sip. They also protect your hand from the blazing temperature some folks like their coffee to be. Many are disposable, often with the logo of the coffee shop (ahem… looking at you Starbucks) emblazoned on them.