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Stock item stock takes have a unit of measure column. Leave it as it comes to count in the unit the item is tracked in, or enter a different unit of the same kind and Breww converts your figure for you. If something is tracked in kilograms and you weighed it in grams, enter 1000 and g, and Breww records 1 kg.
Short forms, long forms and plurals are all understood, whatever the capitalisation, so kg, Kilogram, grams and fl oz all work. The full rules are documented here: Breww | Stock takes | Help guides
More on this and the other stock take changes here: Stock takes just got much easier to run