HOT ROLLED STEEL BEAM SIZE DESIGNATION LB- 75, WEIGHT GREATER THAN EQUAL TO 6. 1 KG PER METER, HOT, ROLLED STEEL BEAM SIZE DESIGNATION MB- 150, WEIGHT, GREATER THAN EQUAL TO 15. 0 KG PER METER, ROLLED STEEL BEAM SIZE DESIGNATION MB- 175, GREATER THAN EQUAL TO 19. 6 KG PER METER, ROLLED STEEL BEAM SIZE DESIGNATION MB- 200, GREATER THAN EQUAL TO 24. 2 KG PER METER