What percentage of the original 1kg of chocolate was used to fill these boxes?

In a chocolate factory, a machine takes a 1 kg block of chocolate and divides this into rectangles each weighing 10g. These rectangles are then stamped into disks of chocolate each weighing 6g with the remaining chocolate discarded. These chocolate disks are then packed into bags of 4 which are sealed and finally packed into boxes. Each box contains 6 bags ready for dispatch to the shops. Find out how many full boxes we get out of the original 1kg of chocolate.