Armachillo V-Neck T Shirt Takes The Simmer Out Of Summer When the weather's hotter than a mouthful of habañeros*, wear a cool-to-the-touch Armachillo® Longtail T® Shirt instead of cotton. The 92% polyester/8% spandex knit is lightweight (just 4.4 oz./yard), soft, comfortable and quick drying – but what's really amazing is this shirt's made-in-the-jade technology. Every fiber is infused with microscopic jade that dissipates heat on contact. So this tee feels chill to the touch – even on days so hot the hens are laying hard-boiled eggs.