I looked up the website and the patent is 'pending'.
Just for fun, some prior art which I know of ....in ballet, it is well known (and decades old) that some girls make their leotards more discrete (and warmer) by taking a pair of tights (usually which have develped holes in the toes), cutting the legs off at the knees, cutting the crutch out and wearing it under the leotard so that the tights cover their arms, head through the enlarged crutch. You might be laughing, but is an accepted look.
Depending on how the claims read, its basically the same thing. Pity, its a great concept which is nicely thought out.