Mr. Chilly is a long pouch with a fold-over flap, made of cushy worsted cotton to insulate skin from the frozen chill of reusable cold packs.

Use an optional button to secure the flap on the outside of the pouch, or just tuck the flap inside, as with the cold pack’s thin original liner.

A shorter pouch would also suit a bag of ice cubes, if that’s your preferred injury-chiller.

I love reusable cold packs—they’re soft and squishy, and enclosed in durable plastic to prevent leaks and drips. But the covers they come with are too thin to really insulate my skin from the direct chill of a frozen pack. Hand-knit washcloths worked much better, but the coverage wasn’t quite right, and cold packs tend to escape. The solution was clear – my cold packs needed their own little envelopes.