chamfered corners on one side to prevent the user from plugging it in incorrectly. The connector that provides power (e.g., on a power supply) has female pins and a male housing; the connector that receives power (e.g., on a peripheral) has male pins and a female housing. The connector is standard on all 5.25-inch floppy drives, 3.5-inch PATA and non-SCA SCSI disk drives; however, newer SATA disk drives employ a more advanced interconnection with 15 contacts. These advanced connection systems were first developed by Molex and other connector companies, often working together to develop interconnection standards. As SATA becomes more prevalent, Molex connectors can be found repurposed, through use of an adaptor, to serve as six-pin PCIe power connectors to make up for a lack of such connectors on a power supply. Lower power devices (e.g. 3.5-inch floppy drives) use the smaller AMP 171822-4 connector instead. Despite its widespread adoption, the connector does have problems. It is difficult to remove because it is held in place by friction instead of a latch, and some poorly constructed connectors may have one or more pins detach from the connector during mating or de-mating. There is also a tendency for the loosely inserted pins on the male connector to skew out of alignment. The female sockets can spread, making the connection imperfect and subject to arcing. Standard practice is to check for any sign of blackening or browning on the white plastic shell, which would indicate the need to replace the arcing connector. In extreme cases the whole connector can melt due to the heat from arcing. See also Electrical connector DC connector Berg connector JST connector CMOS rechargeable battery References External links DC power connectors Computer connectors Koch Industries