The Daikin BPMKS048A2U 2-port branch box is for use in Daikin multi-zone mini split applications. It is used in conjunction with the RMXS48LVJU outdoor condenser and other branch boxes to provide cooling power to up to 8 indoor units at the same time.

This item will connect 2 indoor units and is rated for a maximum connection combination of 48,000 BTUs and for a minimum of 7,000 BTUs. Depending on how many indoor units you will be installing, the correct size distribution unit needs to be installed. 

There is no need to use all the ports available at the time of your initial installation. If you think you will be adding additional indoor units in the future, you can "cap off" the unused ports on the branch distribution units until that later time.