LIGHTWEIGHT YET HARD SHELL】The outer shell of the luggage is made of 100% PP(polypropylene) material, which is Eco-friendly & Anti-scratch, lighter, stronger and durable enough to withstand the rigour of modern transport and provides the best protection. Kono PP luggage goes through strict quality control test, like Drop loading test, Lifting test of handle, Wheel rolling test, Zipper test etc.