It is a 3-way briefcase in A4 format that can be carried in 3 different ways: over the shoulder, over the shoulder or as a backpackhe. The interior is equipped with a convenient clear pocket for storing small items. The main compartment has a zipper that opens in a u-shape. It is a functional item that is easy to use even when carried on the back. The «Tanker» series, which was announced in 1983 and is a key series with Porter. It uses an original 3-layer structure fabric of the US Air Force flight jacket MA-1. The 3-layer fabric of nylon twill (surface) + polyester cotton (middle layer) + nylon taffeta (back) is very light.