we can produce all kind iron manhole covers and frames,example dia.300,400,500,600,700,800,1000,and 400*400,500*500,600*600 and so on,we all can produce for you accroding your request.We would like to establish good business relations with all friends both home and abroad on the basis of equality and mutual benefits. Please feel free to contact us for more to discuss. Give us an chance, we will do our utmost to meet your requirements.