Basically it comes down to this:
Copperhead’s Scenturion Scent Control Technology utilizes a unique and proprietary copper fiber process that permanently binds copper to the fiber matrix of polyester, nylon or re-cycled polyester fibers. These copper fibers are designed to provide natural anti-odor, hygienic protection and enhance the appearance of skin texture against micro-organisms such as bacteria and fungi for the wearer.
Copper metal is shown to be more effective than silver at any temperature. A recent study completed at the University of South Carolina states that silver was only effective with its antimicrobial abilities at temperatures above 93 degrees and humidity above 90%. Copper however, was shown to maintain its antimicrobial efficacy at normal temperatures typical of everyday indoor and outdoor environments.