Ironlace™ Boot Laces are made tough to withstand the harshest environments on earth. Ironlace™ is quite simply the strongest boot lace in the world!.Police, Firefighters, EMT, Ironworkers, Welders, Hikers, construction workers, machine operators, oil miners, tree fallers, millwrights, and marines. If your job is demanding, the Ironlace is made for you.