In my PC each HDD tray has a cable with a SATA power connector. In order to provide a plug-in board with power (see nis Reviews: 'Power Adapter S-ATA 15Pin Male to 4-Pin Molex connector' and 'InLine® power extension internal, SATA plug / socket, 0.5m') it was necessary to install above branch ,
Since these fulfilled their function, they got 5 stars.