Originally Posted by
Scots_Al
That's a very Anglo-centric view of what constitutes the U.K.!
In the civilised parts, a standard measure is 35ml, double 70ml.
Both 25 & 50ml, and 35ml and 70ml measures are legal in the UK as a whole. A measure used to be 1/6 gill in England and 1/5 gill in most of the rest of the UK, and England got stiffed as most places went to 25ml, which is less than the 28.7ml in 1/6 gill.