Our newest products, such has JBL Pulse 4 and JBL Flip 5, feature a new technology called Partyboost .

Partyboost technology

• Improved Bluetooth connection between speakers.
• A more powerful Bluetooth transmitter means that the speakers can be farther apart.
• Partyboost can only connect to other Partyboost speakers.

All newer Portable products from JBL will have Partyboost integrated.
Unfortunately, this feature is not backwards compatible with  previous models that have JBL Connect or Connect+.