Yes, that's exactly what you think it is.
That little triangular piece of cloth aka the Jewel Warmer is said to keep your boys warm during those frosty winter months.
Made out of plush velour fleece, it's said to be windproof yet breathable and can be removed once you're sporting some schweddy balls.
The product costs $14.99 or you can save your money and man up!
[Image courtesy of Jewel Warmer.]