This briefcase has a very handy format. The material of choice for this bag is polyester and it has a 14.5-litre volume.
From Viking Direct
Samsonite Briefcase GuardIT 2.0 15.6 Inch Polyester Black 40 x 9 x 30 cm
The product is available from £48.68 at international stores.
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Laptop Case Samsonite Guardit 2.0 15,6" Black 90 x 40 x 30 cm
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Laptop Case Samsonite Guardit 2.0 15,6" Black 90 x 40 x 30 cm