... surface is zinc-plated , beautiful and anti-oxidant, can long run . Hygieneimmunity , turnover , deposit and is it pollute the environment ... , piles high by forklift truck ,crane ,driving a vehicle , lift , a car , hydraulic pressure tray car ,etc., save time and save effort . Envelope ... standard, can use with the container together . It is a regeneration product of the wooden packing box.