This Task will execute a custom expression you could create. This allows you to calculate for example weight of all related products very easy.
You also could select which products should be used to execute the expression with a simple condition.
You could use special variables during the expression, which are loaded from the Inventory Record (Invoice,…)
| $quantity | Will contain the Quantity of this inventory item |
| $unitprice | Will contain the Unit Price of this inventory item |
| $discount_amount | Will contain the static discount amount of this inventory item |
| $discount_percent | Will contain the percentage discount of this inventory item |
Also you could access every Field of the used Product Record.