Hex has unveiled its new Sport Watch Band for the sixth-generation iPod nano. Made of perforated silicone for added breathability, the Sport Watch Band is designed to be used with the Nike+ Sport Kit, and features open access to the Dock Connector, screen, and headphone port, and integrated push-through coverage for the power and volume buttons. Hex’s new Sport Watch Band for the iPod nano 6G will be available in April; pricing has yet to be…