Compatible in what way? To group? To run on S2 app? To bond surrounds? 

If you want to add surrounds you need two of the same model speakers, but not portable ones as they cannot operate as surrounds. 

I understand so I should buy another speaker one sl? I only have one.and I can't combine it with the Play5?

I understand so I should buy another speaker one sl? I only have one.and I can't combine it with the Play5?

If you want a stereo pair the speakers need to be the same model (but One and One SL are compatible). If you want surrounds the speakers need to be the same model (but One and One SL are compatible). You cannot pair One and Play:5. You can group a One and a Play:5. 
 

I hope that answers your question. If not, I ask again: what are you trying to do? 

Ok i understand thank you!