For its newsletter subscribers only, newegg offers the ASUS Selectable Dual-Band 802.11ac / 802.11n Wireless Adapter, model no. USB-AC53, for $49.99. Coupon code "EMCXRVS79" cuts it to $39.99. With free shipping, it's the lowest total price we could find by $8. It features WEP, WPA, and WPA2 encryption. Deal ends May 27.