I attempted to correlate ounces (US) to its metric equivalent in milliliters (UK). No conformance was achieved to a "standard" metric fluid measurement.
Fluid Ounce. A fluid ounce is approximately 30ml of liquid in both the US and UK. However, the exact value in the UK is 28.4ml and 29.6ml in the US.
11.5 oz (US) ==> 340.1 ml (US)
The metric value, as seen etched on glass throughout Europe, has decimal equivalents of the liter as:
0.33 l
0.50 l
1.0 Liter
etc.
So, an 11.5-ounce (US) beer is about 0.33 liter (326.6 ml) in the UK, which is the Beer Maker's "close approximation" to the metric system.
It hurts my head...