As a reader discovered, Linksys Store offers the factory-refurbished Linksys 802.11ac Wireless Dual-Band AC1200 USB 2.0 Adapter, model no. WUSB6300, for $29.99 with free shipping. That's $17 under the best price we could find for a new one. It features support for up to 128-bit encryption. A 90-day Linksys warranty applies.