aluminium extension ladder 13mtr fully extended 8 00 mtr 8 00 mtr made of high tensile alumin ium alloy c section 66x32x3 16 mm thickness of ohe 30 grade as per is 733 1983 t6 temper of hindalco mak e steps will be made of 28x3 mm square corrugated tubing fitted on distance of 250mm 10 inch centre to centr e width of extension ladder min 310 mm approx ladder will have fixed rubber pads and hook on top of the lad der hook made of ms flat 32x5 mm hook bending on 5 mm pulley bracket complete with