... rolling door is rolling ups and downs,do not place sundry articles under the rolling door ... quality is root in perfect material . To our motor we use : 1 .6 pole winding in stator coil 2 ... stable, bigger moment , lower noise , can be use 20.000times 4.The Characteristic for contorl part :Using ... maintain , suitable for operate frequency , can be use more than 100,000 times .Besides with the lightning ...