Explain the tax rate
Show the tax class of the size a shopper picks.
Each example below is the actual published output of the Variation tax class label widget for a sample product, Refined linseed oil: 250 ml in the standard class, 500 ml and 1000 ml in the Reduced rate class. On a product page the value changes to the size the shopper picks.
Prefix VAT: before a choice, when sizes are in different classes: VAT: Varies by option.