The Backpack fee applicable for items according to price range is:

Item price | Backpack fee |

$0-$500 | 21% |

$500-$1,000 | 18% |

$1,000+ | 15% |

A weight / dimension (W/D) charge added to an item's price means that the item's shipping weight or volume occupied in the traveler's luggage, is relatively high compared to its price. As a result, W/D charges had to be added to the standard 21% Backpack fee.

Additional charges are applied according to the rates given below:

Shipping weight rate: $7/lbs

Dimension rate: $3.4/ltr

From among the three values: standard Backpack fee, shipping weight charge, and dimension charge, the highest value is applied as the payable amount in your invoice.

So if an item is priced at $100, weighs 4 pounds and has dimensions as 15"x18"x12,"

Total shipping weight charge would be:

Item weight X Shipping weight rate = Total shipping weight charge

4lbs X $7/lbs = $28

The Dimension charge is calculated as follows:

- Item dimension:

- The total dimension for a standard luggage: 88.5 litres (25"x18"x12").

- The total cost for the luggage: $300

- The item's total dimension charge is then calculated as:

- Item dimension / Standard luggage dimension X Total luggage cost = Item's dimension charge

- (15"x18"x12") / (25"x18"x12") X $300 = $180

So the three values are:

- Standard Backpack fee: $21

- Shipping weight charge: $28

- Dimension charge: $180

Given that the item's dimensions are affecting the luggage capacity the most, we'd calculate W/D charge as:

- Dimension charge - Standard Backpack fee = W/D charge

- $180 - $21 = $159

The item's total price would then be calculated as:

- Item price: $100

- Standard Backpack fee (21%): $21

- W/D charge: $159

- Sales tax (9%): $9

- Total price: $289

If on the other hand, total shipping weight charges or dimension charges add up to less than 21% Backpack fee, in that case, only the Backpack fee will be taken into account. According to this pricing model, items that are expensive but are small and weighs little will be treated fairly. Apart from these, prices of most other items will remain the same. Happy Backpacking!