1 box = 1 staircase complete with 12 steps Structure, Steps, Railing (internal side), Handrail
Choice between:
Straight staircase: 12 straight steps
Staircase with 1 turn: (2 versions) 9 straight steps + 3 turn steps or 11 straight steps + 1 landing
Staircase with 2 turns: (2 versions) 6 straight steps + 6 turn steps or 10 straight steps + 2 landings
Box measurements may vary