Echo Sub – Powerful subwoofer for your Echo – requires compatible Echo device

Price: $129.99
(as of Jan 25,2022 11:05:54 UTC – Details)

Pair with one Echo device to enjoy dynamic music that fills the room.
Pair with two of the same Echo devices for rich left/right stereo sound.
Simple to set up and use—just plug in, open the Alexa app, and wirelessly connect to your Echo device(s) to control music with your voice.