D-Link DAP-1520 User Manual page 23

Section 3 - Configuration
You can also use the WPS button on the side of the DAP-1520 to
initiate a WPS connection with the uplink router. After pressing
the WPS button on the DAP-1520, you will have 120 seconds to
press the WPS button on your access point or router. The LED on
the DAP-1520 will turn solid green when a connection has been
successfully established with the uplink router.
Once your connection has been established, you can then enter
your desired extended network settings for both 2.4 GHz and 5
GHz networks. Click Next to continue.
D-Link DAP-1520 User Manual
WPS Button
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