This is a 4℃ strap. It's one half of a pair strap, and when the two are put together, the space in the middle forms a heart shape. It has the engraving "Two's favorite things 4℃". It's a rectangle measuring 1.5 x 3.5 cm. I found it while decluttering, but I don't remember when I got it. It's only one half, but if anyone wants it, please do.