From CIOKS:
"Type 4 Flex cables are green and fitted with a centre positive 5,5/2,5mm DC plug. This Flex cable type is nowdays mainly used to power all Eventide Factor and H9 pedals and is widely used for many AC pedals. This Flex cable is available with angled (L-shaped) plug in three lengths 30, 50 or 80cm.
The applications we know are the following pedals:
* For AC pedals polarity doesn’t matter! There’s nothing like a DC or AC cable. Power cables just have a negative or positive polarity which in case of alternating current doesn’t matter. If your black Flex cable doesn’t fit into your AC pedal’s socket you should use the green one which is for the larger 2,5mm pin. Minimum one green Flex cable is included with all our power supplies except the Adam link. You can also get a yellow type 3 Flex cable for your AC pedal and have the green ones to power your Eventides."