Vulcan pile extractors were largely designed to extract sheet piling. The standard connection had two (2) or three (3) holes that needed to be burned into the sheeting. While this provided a very durable connection, it was time consuming and is not really applicable to piling such as wood piling.
Above is a diagram, taken from Vulcan’s literature around 1960, showing various types of pulling adapters for piling other than sheeting. In addition to these there were two other types of connections that were used on Vulcan extractors: