Please note that the couriers record the actual weight, as well as the volumetric weight (length x width x height / 4000) of the parcel when it moves through their cage. The courier will then bill the customer for the shipment on the bigger of the two weights.
The uAfrica system uses your weight entries to work out your quote (Estimate Charge) based on the larger of the two weights, the same way the couriers do.
For example: the Estimate Charge for a parcel was calculated on the (standard sleeve) dimensions of 42 x 38 x 5 cm = 1,9 kg volumetric weight, but the courier measured dimensions of 39 x 29 x 13 cm = 2,9kg (volumetric weight). If the actual weight of the parcel was 1.7kg, the billing will done by using the volumetric weight of 2.9kg, based on the actual dimensions of the parcel. This is why the Final Charge for a specific waybill may be more than your initial Estimate Charge.