Structures and parts of structures of iron or steel nes excl bridges and bridgesections towers and lattice masts doors and windows and their frames thresholds for doors props and similar equipment for scaffolding shuttering propping or pitpropping

Could you correct the punctuation please?
Structures and parts of structures, of iron or steel, n.e.s. (excl. bridges and bridge-sections, towers and lattice masts, doors and windows and their frames, thresholds for doors, props and similar equipment for scaffolding, shuttering, propping or pit-propping)