You could also wall-mount it so long as you pay extra ... is paired with Era speakers as rears. The Sonos Arc Ultra can be paired with Era 100 or 300 speakers, for rear left and right channels.

Best rear speaker add-on The Sonos Era 300 is built to work as a stand-alone wireless speaker or as an add-on speaker for select Sonos soundbars. Two Era 300 units can be paired together and used ...