Rosewill RNX-N150PCe IEEE 802.11b/g/n PCIe Wireless Adapter for $7.49 Shipped
Rosewill RNX-N150PCe IEEE 802.11b/g/n PCIe Wireless Adapter for $7.49 shipped after code EMCNJNJ222. Here is a screenshot for your reference. It goes up to 150Mbps and uses all the standard and common security protocols. It is a rather inexpensive way to add wireless connectivity to a PC.
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