Pocket Bike Chain 25H series aka HS25 Series. Total link length is 1.1cm, outside width is 7mm and the inside width is 3mm. This is a 168 pin, 84 link chain.
35 Chain - 100 Links
35 Chain - 140 Links
35 Chain - 160 Links
410 Chain - 100 Links (101 Pins)
410 Chain - 110 Links (111 Pins)