Instruction of the assembly of stairs on concrete base.
Drill four holes φ 10 on a concrete basis, 50 mm deep
Insert tags into drilled holes and hit lightly on a step from above, using rubber hammer.
Mark the spots for drilling holes in the step
Drill four holes φ 14 in a wooden step, 25 mm deep.
Push the dowels into the holes in concrete, level the step using pads and screw in the screws.
Apply polyurethane foam and stick the step on the dowels.