A unit of volume for beer in Western Australia, equal to 115 milliliters (4 Imperial fluid ounces). This quantity is a smaller version of the 5-ounce pony; its name refers to Shetland ponies, small horses from the Shetland Islands north of Scotland
Russ Rowlett (Director), How Many? A Dictionary of Units of Measurement, Center for Mathematics and Science Education University of North Carolina, USA 2005. http://www.unc.edu/~rowlett/units/dictA.html, (Unit of Meas and Covr Factors - Amer) {608}