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I have a Netgear A12X RAX120 AX6000 router, and use the X6S EX8000 AC3000 Extender. The extender is a tri-band with two 5 and one 2.4 band. The extra 5 band is used exclusively to talk to the router, and the other 5 band exclusively sends out the signal to the devices. Speeds are great. Just make sure you put it between the router and the device, and not next to the device you need more bandwidth at.
 
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