Amazon offers the TP-Link Archer T1U Wireless Nano 802.11AC WiFi USB Adapter for $18.99 plus you get Free Shipping with Amazon Prime or on orders over $49. You save 17% off the list price. This has 3,347 Amazon customer reviews with a rating of 3.9 out of 5 stars.

• Tiny and unobtrusive design allows you to plug it in and forget it
• Data transmission rates of up to 433Mbps
• Utilizes 802.11ac standard and is backward compatible with 802.11a/n
• Transmits on only 5GHz band to avoid wireless signal interference
• 2-year warranty and unlimited 24/7 technical support