US gills
A US gill is a unit of volume in the United States used for measuring liquids. One US gill is 1/4 of a US pint or 118.294 milliliters.
UK fluid ounces
A UK fluid ounce is about 28.41 milliliters, a little smaller than the US fluid ounce of about 29.57 milliliters. So 1 US fluid ounce is about 1.04 UK fluid ounces.