Officially they are two different speakers that sound differently and you should.
Unofficially - many people think they are close enough to the same and wish to pair them. There is an ios app called Sonosequencr that will pair them as stereo pair (will pair any two sonos speakers no matter the model) or set them up as rear surrounds in a 5.1 system.
Respect the Queue (2)Move (3)Beam (1) Era100 (2)ARC (1)SonosOne (1)Playbar (4)Play5 (4)Play1 (3)Play3 (1)Port (2)Connect (1) Roam (2) Ace (1)Connect:Amp (4)Sonos Amp (1)Sub + (9) Echo + Smartthings; (2)Play)