This attribute specifies your priority of the denominator of the unit price.
The usage is recommended if you use the attribute unit pricing measure.
Numerical value + unit
You must use the same measurement for the attribute unit pricing measure and 'unit pricing base measure'. In case you use the unit kg for one attribute you must use the same for the other one. To use the attribute correctly your value has to be 1, 10, 100, 2, 4, or 8. Furthermore 75cl, 750ml, 50kg, and 1000kg are accepted. You must submit an integer value because the system will not accept it otherwise.
Note that Google Shopping shows a different base measure in your ads to make the unit prices more comparable for all ads shown on the same page.