The Short Sleeve T is made with a cotton/poly blend woven with silver fibers. Tested between 10 MHz and 4 GHz, this T-Shirt shields radio frequencies an incredible 45 dB (99.997%). A great way to protect your upper body, while staying cool. If extra warmth and/or shielding are required, see our Long Sleeve T and Hooded T below. Available in Gray, Black, and Pink. Specify desired size: S M L