TP-Link TD-W9970 User Manual page 37

TD-W9970
Click Advance, advanced selections for WAN Service Setup can be shown.
 MTU (Bytes): Maximum Transmission Unit Size. Check this box then you can change the
MTU size. The default MTU value is 1500 Bytes. It is not recommended that you change the
default value unless required by your ISP.
300Mbps Wireless N USB VDSL2 Modem Router User Guide
Figure 4-12
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