Newegg offers the refurbished ASUS Selectable Dual-Band 802.11ac / 802.11n Wireless Adapter, model no. USB-AC53, for $39.99. Coupon code "EMCPCWB43" cuts it to $29.99. With free shipping, that's the lowest total price we've seen for this adapter without rebate hassles and $20 below the lowest total price we could find for a new adapter. It features WEP, WPA, and WPA2 encryption. Deal ends July 20.

A 1-year warranty applies, but it's unclear who backs it.