4 pin is the size that connects to the camcorder , and 6 pin the sfirewire slot thats o0n the compuyter, the one that looks like a usb slot with a diff shape,,, youd probably need a 4pin - 6pin cable,,, ,, thats what i have,,, some laptops ahve the 4 pin slot to sace space so thats why there are 4 pin4 pin