You can connect a Flip 6 to the Flip 5, though, since these both use the PartyBoost standard. Likewise, for the JBL Charge 3 and Flip 4 Connect+ speakers. Here’s a list of compatible JBL ...

Through the JBL Connect app, pressing the PartyBoost button on the Flip 5 helps you pair two PartyBoost-enabled speakers to create a stereo pair, or to link over 100 PartyBoost-compatible speakers in ...