Laptop backpack trolley backpack capacity 34 litres weight 25 kg height 50 cm width 34 cm depth 20 cm max laptop size 154 inch features organiser padded back internal pockets laptop pocket outside pockets front pocket mesh side pockets straps tuck away harness compression straps bag feature suitable as cabin luggage iata norm material synthetic fiber fabric specification 420 d nylon inner material synthetic fibre material properties water rep