You have the option of maintaining weight- or volume-dependent conditions. The condition types for weights and volumes are then taken into account during the purchase price determination process.

You can maintain the Gross weight and Volume fields in the additional data for the item.
Both fields relate to an order unit. This means that if you order 100 pcs. of material A, for example, and one piece weighs 10 kg, the Weight field contains the figure 10 kg (not 1000 kg).