Steel Props, High Quality Steel Used, Hardened Couplers are Adopted, Heavy Duty Steel Props Steel props (light duty) I: 1,920-3,500mm, ... -3,900mm, 28.66lbs2,920-4,500mm, 32.19lbsSteel props (light duty) II: 1,920-3,500mm, 27. ... -3,900mm, 29.98lbs2,920-4,500mm, 33.51lbsSteel props (heavy duty) I: 1,700-2,900mm, 54. ... -3,900mm, 66.14lbs2,700-4,900mm, 77.16lbsSteel props (heavy duty) II: 3,251-4,877mm, 59. ...