I've been using the Pro traverse tool to digitise some survey plans from the 1960s. The plans state they were recorded in British Feet. Using the traverse tool there are two options for feet. Knowing that many options for feet exist (Olympic foot, US survey foot, British foot etc) I'd like to know which options are presented here. Both are referred to as "ft" in the tool and I can't find anything in the docs to differentiate the two. See the screen shot below for clarification.