Initially the rules of SATA cables and connectors defined a 7-pin connector for data and one 15-pin connector for power. SATA connector format SlimLine is the evolution of SATA connector to a smaller size, eliminating unnecessary pin power connector (15-pin to 6-pin) and compacting data and power in one connector. Used in ODD (Optical Disk Drive) and HDD (Hard Disk Drive) laptop or desktop computer.