Black Iron Square Tube ihe bụ oyi akpọrepu carbon ígwè eriri na mgbidi ọkpụrụkpụ 0.6mm ka 2.0mm.Mgbe eriri igwe na-ekpo ọkụ na-ekpo ọkụ na-ekpo ọkụ na-ekpo ọkụ na-ekpo ọkụ na-ekpo ọkụ, agba elu ga-agbanye oji n'ihi ikpo ọkụ dị elu na ikuku.A na-akpọkwa oyi akpọrepu black annealed square tube nke a na-ejikarị arụ ọrụ nchara.