BTX motherboards use a 24-pin power connector.
Parallel ATA connectors use a 40 pin female connector with one pin removed for keying.
Parallel sockets are wide, with two rows of pins that total 25 in all. Printers and some other devices use 36 pins, but they look the same. There is a screw hole at either end to allow the connector to be fastened securely.
Notebook's use 2.5 hard drives and they have 44 pin connections 3.5 hard drives used 40 pin connections BUT they make adapters to use either or
DDR SDRAM uses 184 pins.
The berg has 4 pins And is a male part..the MOlex has 4 pins and is a female part..
The beauty of SCSI is that supports many physical interfaces. Fibre channel SCSI uses 4 "pins" which can be copper, or fibre optic cabling. Parallel scsi which you are probably asking about can use 25, 50 or 68 pins. So you should rephrase your question to specify the interface you are asking about ... but I guess that would liook kinda dumb, ... "How many pins does a 50-pin SCSI interface have" :)
4 pins 2 for power supply and 2 for data transfer!!
EIDE
The number of connectors will depend on which version of this serial bus interface you are considering. It will have either 4, 6 or 9 circuits (pins) depending on which "flavor" of the FireWire standard you are applying. Use the link below to review the standards and look at some pictures.
Some use straight pins into back of connector or a tester that will pierce the wire so you can probe while it's plugged in.
The trailer lighting connector is located behind the left side panel in the cargo area. If you use a converter, you can get the connector and pins that mate with the connector in your vehicle from a dealer. Since lighting and wiring vary with trailer type and brand, you should also have a qualified technician install a suitable connector between the vehicle and the trailer. See related link below.