Buffalo AirStation Draft-N WZR-G300N User Manual page 89

125* High Speed Mode
* When operating in High-Speed Mode, this Wi-Fi device achieves an actual
throughput of up to 34.1 Mbps, which is equivalent to the throughput of
a system following 802.11g protocol and operating at a signaling rate of
125 Mbps.
270 Mbps is the link speed when using Draft-N mode. It represents
actual wireless data speeds, including overhead. Because the overhead
is not available for user data transfer, usable wireless throughput will be
substantially slower.
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